A watch movement's frequency is measured in vibrations per hour or Hertz(Hz). This frequency is based on the number of oscillations per second and is also known as A/h.
Horologist born in 1947 in Switzerland. Responsible for many innovations and designs still being used today. Also known for his impeccable watch designs and is hailed as the foremost watchmaker of his time.
The "mean daily rate" refers to how accurate a watch is. This depends on the movement of the mechanical watch. It can vary slightly on a day to day basis reducing the accuracy of the watch. The overall accuracy can change under a number of conditions. This means over time, the watch can lose or gain time measured against the atomic standard time.
A soft plastic used to make crystals. It is easy to repair. If it breaks, it doesn't shatter. Acrylic crystals are particularly used by watches designed for use in space.
A crystal made from acrylic. These are effectively plastic crystals.
When a watch is indicated ad being “adjusted” this means that it underwent testing while being assembled to ensure a minimal loss pr gain in time. The watch will be caibrated using a minimum of nine adjustments which include step-up, stem-down, stem-left, stem-right, face-down, face-up, isochronism, heat and cold. This ensures a qia;ity timespiece that functions flawlessly in a variety of environments.
These adjustments are Crown up, Crown down, Dial down, Crown left, Crown up, Crown right. Watches are tested adjusted in 2 to 6 positions to improve accuracy across orientation of the watch.
Care has been taken to adjust accuracy based on a variety of orientations of the watch.
Both mechanical and quartz watches allow for an alarm setting. Inside the movement, a second mainspring can activates a small component resulting in a weight vibrating back and forth resulting in a vibration or noise at a specific time. This is referred to as an alarm.
A device which is set by a program or system to make a sound or vibrate at a particular time or times.
A watch that allows for an alarm to be set for a pretermined time.
A device that responds to changes in barometric pressure. This is used to determine altitude.
Also known as a day and night indicator, this indicator allows the person wearing the watch to work out whether it is day or night on a 12 hour digital or analog watch.
When the balance wheel inside the timepiece swings back and forth, it ticks or beats. There is a maximum angle the balance is able to swing from rest position. This is referred to as the amplitude. In a horizontal position the amplitude is usually between 275 and 315 degreeand spins to 275 to 315 degrees on the opposite side. Poor amplitude wil lreduce the effectiveness of your watch's timekeeping. That is why it is important to maintain your watch properly.
See Analog-Digital
This is a method of displaying time using hands and markings on a face as opposed to a digital system of displayed numbers. Although this type of readout was out of fashion in the 1980s and early parts of the 1990s, it is once again the more popular choice.
Combining elements of digital and analog displays
A watch that combines both digital and analog elements. There are mechanical versions, but this is more common in Quartz watches.
A display of time using a watch face and hands
A display of time using a watch face and hands
See Analog
A watch that allows for time to be determined via position of the hands on the watch face
See Analog or Analogue Watch
See Analog-Digital Display
See Analog-Digital Display
See Analog or Analogue Watch
See Analog
An anchor escapement is used in pendulum clocks. In a mechanical clock the escapement is a mechanism that maintains the prendulum's swing by causing a small push each time it swings. This allows the clock's wheels to move a fixed amount per swing. It also moves the clock's hands forward. The anchor escapement has a part which is similar in shape to a ship's anchor resulting in the name of this escapement. .
This is the French word for chamfering. This refers to the process of making a 45 degree angle on the edge of an item being worked on.
This is an accurate yearly calendar which had to be adjusted each year at the end of February to keep it accurate. The watch displays date, month and day of the week. typically including the year. Read about different types of calendar complications.
A timepiece which features an annual calendar complication. The day of the month is adjusted following months of 30 to 31 days but requires manual calibration in February.
See Antireflection
A device that does not show any effect when exposed to magnets or magnetic fields
Mechanical watch movement designed to withstand the effects of magnetic fields
See Antireflection
An optical coating that is appliced to any optical surface to reduce glare. It is referred to as antireflective or anti-reflection (AR) coating as it reduces the amount of reflection a surface gives off.
An opening in the display which shows information such as a moon phase, day, date, month etc.
This refers to raised metalbatons or numbers which are attached to the dial via pegs or adhesive.
Applied or appliqué chapters are symbols or numerals which are cut out of a sheet of metal and are then riveted or stuck on to a dial.
1, 2, 3, 4, 5, 6, 7, 8, 9, 0
The axle that moving part of the watch rotate on is known as an arbor.
Ardillon buckles are also called Tang buckles. These are traditional buckles where one end of the strap goes through a buckle. There is a pin which secures the watch to place so it stays on your wrist.
Another word for silver dial.
Tonneau, barrel and rectangular watches are generally inspired by the art deco style of the 1920s and early 1930s. This is a particular design style related to that era.
An asassortment is a French term related to the parts used in making an escapement
The actual process of fitting together all the components needed for a movement. This used to be done exclusicely by hand, today this is mostly automated. The human element is still required for testing and inspection of the finished items though.
See Assembling
An atmosphere is 1 unit of pressure based on the standard atmospheric pressure experienced at sea level. One atmosphere is the worked out as the pressure of 1kg/cm2 and this corresponds to 10 meters of depth. This is displayed as a value to indicate water resistance such as 10ATM.
ATM or atmosphere indicates how water-resistant a watch is.
Atomic calendar is a complication which takes leap years and varied month lenghts in to account. A few of these can actually be pre-programmed for up to forty years into the future without any adjustment being required.
The most accurate timekeeping device on the planet is known as the atomic clock. This clock only loses around 1 second every 1.4 million years. It broadcasts a signal which can be used to sync watches for ultimate timekeeping. This clock utilizes vibrations of atoms in a metal isotope. An atomic watch needs a user to set their timezone and relies on radio transmission from the atomic clock for its timekeeping accuracy.
The atomic clock measures the electromagnetic signal emited by the electrons in atoms as they change energy levels. This is used to ensure accuracy of timekeeping where only 1 second is lost in a 100 thousand year period.
This allows for an error of only 1 second in 100 000 years.
An atomic watch never needs to be set for time or date as it is set via radio signal each day by synchronizing with an atomic clock.
A manufacturer or retailer appointed by the original manufacturer or distributor to sell directly to the public.
This is a countdown that starts a countdown immediately after the stop button is pushed, on reset and repeat basis.
Patented perpetual movement by Rolex, invented by Emil Borer in 1931
A setting which automatically illuminates the dial via the backlight when your wrist is tilted towards your face when it is activated.
A mechanical watch that does not need to be wound by twisting a crown but rather by the wrist movements of the person wearing it. The movement of the wrist moves a counterweight in the watch. This powers the mainspring, which in turn powers the gears.
Automatic quartz is a universal term that describe the way a watch moves that includes a rotor mechanism that winds itself (as used in automatic non-digital watches), to create electricity with a piezoeletricquartz crystal as it's timing component.
Is a version of a mechanical watch. The watch gets wound by the movements of the wrist of the person that wears it. An automatic watch can be wound down by rotating the crown manually.
Is a container with slots that are motorized to hold the watches that work with automatic movements. The circumrotation keeps the watch wound by oscillating the movement's rotor accurately by counter balancing the effects of gravity. Certain winders are placed in to secure safes that are specifically made to hold collectible automatic watches that are valued in the six figure range.
This refers to self winding that happends through the movement of the wearer's wrist, as opposed to manually winding the watch. An automatic watch that hasn't been used for a while will need to be wound to be able to use it.
Also referred to as self-winding or simply automatic. A mechanical watch is wound by the wearer by occillating a weight or by twisting a rotor. The power cache does diminish completely if the watch is not worn on a regular basis, which can prove rather annoying.
Automatic watches have a small ocillating weight within the movements with moves around when the wearer's a natural actions, which tightens the spring that runs the watch. The active movement during a period of approximately 6 to 10 hours should build up enough winding cache to allow the wearer to place it on their wrist in the morning. If the watch hasn't been used for approximately 24 hours, you will need to wind it again. Your automatic watch can be manually wounding it 5 - 8 complete revolutions and then put it on. Then program the correct time and wear it as per normal. The automatic watch can be limitlessly wound with no damage to the timepeice, however, winding more than 30 complete 360-degree turns will be sufficient to fill the power cache and any more winding will be pointless.
An automaton is a machine that operates itself, or a control mechanism or machine that is created to automatically follow a sequence of operations that is predetermined, or to respond to preprogrammed instructions.
An auxillary dial is an additional dial on the watches face that can be used for many different indications depending on the complexity that is required.
Backlash, the space inbetween the mating gear teeth, which is built into speed reducers to allow the watches mechanical gears to mesh without sticking together and to provide a clearance for a thin film of oil to lubricate inbetween the teeth. This will prevent tooth or overheating damage.
Oval or elongated rectangular shaped movement in a women's watch
Transparent acrylic used in 1954 on the bezel insert of a Rolex GMT Masters
The oscillator on a mechanical watch controls the movement that works in a series of vibrations or movement
This is the core of the mechanical watch movements. The mainspring provides not only the energy but the balance as well (together with the hairspring), t divide time into equal parts
A bridge where a lug is fastened to a stud. It holds the watch's balance staff on the top pivot.
A fragile spring (mostly made from a mental but occasionally from silicone)., attached to the balance wheel that controls the frequency at which a balance wheel rotates. The balance spring is also known as a hairspring.
A minute spring in a mechanical watch the returns the balance wheel into its neutral position.
Sometimes referred to as a hairspring: the spring governing the balance wheel. It winds and unwinds to swing the balance wheel to regulate time.
The balance staff is the middle shaft on the balance wheel. It has pivots located on the top and bottom, which are very thin points that the balance wheel operates on and is supported by the balance jewels.
The balance staff is the middle shaft on the balance wheel. It has pivots located on the top and bottom, which are very thin points that the balance wheel operates on and is supported by the balance jewels.
An rotating wheel that regulates the movement by dividing time into regular beats
The part of a mechanical watch that rotates and divides time into equivalent portions.
The strap that goes around your wrist to keep the watch in position, more often referring to a leather or rubber band. Whilst referring to watches, it is referred to as a bracelet or strap; not as a band.
The band width is the distance that is measured between the lugs of the strap. When purchasing a new or replacement band or strap it is important to know the measurement, as it determines the size you will need in order for it to fit your wrist watch properly.
Is a unit of measurement that relates to the pressure a watch can with stand. One bar is about equal to the atmospheric pressure at sea level and is approximately 10 meters.
Finish on bezel or bracelet links that resemble tree bark
The barometer measures air pressures and displays tendencies in the weather. As a general rule, the higher a person goes (ascent/terrain), the lower the barometric pressure will be. A drop in air pressure usually means that inclement weather is on its way.
The cylindrical, enclosed apparatus with geared teeth that contains the mainspring, thus houses the watch’s power reserve. A watch’s power reserve can be expanded by adding more barrels.
The drum-shaped container that encloses the mainspring in a mechanical watch. The size of the barrel directly relates to how long the power reserve will hold. A double barrel will increase the power that is reserved.
The modern going barrel that was conceptualized in 1760 by Jean-Antoine Lépine, creates a continuous force by the simple method of using a longer mainspring than required and coiling it under tension in the barrel. In use, only a few turns of the spring at a time are utilized, with the remainder pressed against the outer wall of the barrel. Mathematically, the tension generates a 'flat' section in the spring's torque curve and only this flat section is used. In addition, the outer end of the spring is often given a 'reverse' curve, so it has an 'S' shape. This creates a cache of more tension in the spring's outer turns where it is accessible toward the end of the running period. The end result is the barrel provides constant torque over the watch's designed running period and the torque doesn't diminish until the mainspring has almost run down. The built-in tension of the spring in the going barrel makes it dangerous to take it apart even when not wound up.
A metal such as copper, tin, zinc which are often used in watch making but are not considered precious metals.
Held in Basel, Switzerland in April each year, this is considered to be the largest watch show in the world.
A single cell squat cylinder , usually around 5mm up to 25mm in diameter and 1 to 6mm high. Used to power many types of watches.
The end-of-life indicator on a quartz watch is indicated when the second hand will jump in two to four second intervals.
The length of time a battery is able to provide a charge.
The end of life function is an indicator that warns you of a battery that is soon to go flatin a quartz watch. When the wearer notices the second hand jumping in two to four second intervals this will indicate the battery is about to go into failure within about two weeks.
The watches that are battery-less are powered by the wearer's arm movements.
A recent hybrid technology allows the watch run without winding it or having a battery. While typically using a small electronic dynamo, the watch stores energy in it's own battery, that can be recharged, device which allows the watch to keep time. Usually these watches are known under copyrighted brand names and must be worn on a regular basis similar to that of an automatic watch
Higher quality watches have historically used jeweled movements, which means that jewels (used to be natural ruby ,diamond or sapphire, now synthetic ruby or sapphire), were used in the movement. These jewels are practical, as they are used for the bearings of the wheel trains and in high wear parts such as the escape lever and impulse jewel.
Refers to the vibration or the tick of a watch; about 1/5 of a second. The sound is created by the escape wheel striking the pallets within the watch.
Beat error is an disproportional rotation of the balance wheel. The beat error is the difference between the clockwise and the counterclockwise swing of the balance.The beat error is 0 in perfect conditions.
When an edge is ground, turned or filed to prevent sharp edges the result is known as a bevel.
Changing a square edge on an item to a sloped edge by shaping, grinding, filing or other method of reduction.
A bezel is a ring around the watch face made of stainless steel, precious metal, base metal, ceramic. It can be either decorative or functional. If is the latter, it may be inside or outside the crystal and oscillate to act as a timer, tachymeter, slide rule, or any other function.
A bezel is a typically metal, (though occasionally ceramic) ring that surrounds the watch crystal. Often bezels oscillate on watches (normally on dive watches) and contain a scale for time and or other measurements; some do not move or do not have a scale and are purely decorative. (Learn more about different kinds of bezels here.)
The outer edge that surrounds the dial (face) and retains the crystal. A bezel is often made of precious metals, or a few unique materials. A bezel can be used to measure speed, distance or elapsed time.
The ring around a crystal on the top part of a watch. It is usually made of different metals such as gold, gold-plate, platinum or stainless steel. It also holds the glass or crystal in place.
Introduced by Rolex originally, this is a luminous hour marker which is surround by a circle of white gold. Popular in the 1980s.
See Two-Tone.
A chronograph which has a [air of subdials is often referred to as a Bi-Compax.
A bezel that can be wound clockwise or anticlockwise to perform a function. A Bezel can be used to make mathematical calculations or keeping track of elapsed time.
Bienfacture is a French word with Swiss roots meaning "to make well". It refers to an item of high quality design or manufacture.
A nickname for the Rolex Submariner models which had a 8mm Brevet winding crown.
The date is the simplest complication, in addition to the basic time functions, and it is very useful to be able to see the date at a glance. Several watch brands have solved the problem with the so-called big date function, in which there are two sets of numbers, one for the tens and one for the units.
Black polishing is also known as spéculaire finishing. It is used to finish steel parts in a watchmovement to create a mirror-like surface
The 2 centre parts of a fold over clasp.
This is a slang term for Rolex GMT and GMT II models with blue bezel inserts. These are very rare.
Bluing is also used for creating coloring for steel parts of fine clocks and other fine metalwork. This is often accomplished without chemicals by simply heating the steel until a blue oxide film appears. The blue hue of the oxide film is also used as an indication of temperature when tempering carbon steel after hardening, indicating a state of temper suitable for springs.
Bluing is a passivation process in which steel is protected against rust, and is named after the blue-black appearance of the resulting protective finish
This was a nickname for the Rolex Bombay which had a convex profile, helix lines and particular form of lugs.
A pocket watch has a neck, above the crown and at the top of this is an area where the fob or chain can be attached. This is known as the bow.
This indicates that the watch comes with it's original packaging and certification, guarantee and any accessories.
A box hinge case is a very heavy case with reinforced hinges and heavy metalwork supporting to support the bow/pendant.
This is a watch which is usually around 2mm smaller than a standard men's watch
A band for a watch made of movable metal links.
A bracelet is a metal strap which is used to secures the watch on to the wrist. It uses links that can be removed or added to for sizing the watch to fit correctly.
A Bracelet set is a matching watch and bracelet design which is generally used for ladies evening/formal wear.
This is Arabic numerals in a font designed by Abraham-Louis Breguet
This is a spring created by Abraham-Louis Breguet In 1795. This design improved the rate while reducing the wear on the balance pivots. Most watches now use this design.
See Breguet Overcoil Spring
This means patented and comes from the French "brevette".
A movement plate or bar secured by two or more screws to the mainplate is referred to as a bridge. This creates a frame which houses the inner workings. These can be shaped to give an aesthetic look especially in skeleton watches.
See Bridge
This refers to the hour hand on a vintage Omega sports model such as the Railmaster or Speedmaster
This is stainless steel with a satin or matte finish which is created by polishing and then softening the metal
A finish created by polishing and softening of the metal
The early Rolex perpetual watches had a large auto-rotor movement which was covered by a thick case. These were referred to as bubbleback watches
A case back which is rounded to appear bubble-like.
The buckle also known as a clasp is a device used for fastening two loose ends, with one end attached to it and the other held by a catch in a secure but adjustable manner.
This is a Rolex dial which is painted with large Roman numerals. These were the first dials with Day-date or Dayjust dials done in this manner.
A watch dial which includes lighting to be able to read the time in the dark.
Burnishing is a process that work-hardens a metal surface. It is more often used on pivots to increase their durability and reduce friction.
A Butterfly rotor is an oscillating mass with the characteristic “butterfly” shape used on the Rolex 1030 and 1530 calibers and derivatives until around 1963.
Backlash, the space inbetween the mating gear teeth, which is built into speed reducers to allow the watches mechanical gears to mesh without sticking together and to provide a clearance for a thin film of oil to lubricate inbetween the teeth. This will prevent tooth or overheating damage.
Bienne Rating Office
Is the most popular and largest wristwatch show in the world. It is is usuaylly held every year, for six days in the spring. It attarcts approximately 80,000 visitors and over 3,000 journalists.
The authoritative Swiss Chronometer Testing Institute puts every chronometer watch through a rigorous, 15-day testing procedure to verify the watch's precision.
Cabochon is a precious stone, polished but uncut. Cabochon is a French word that is also used for an embossed ornament on a dial, a fancy gilt nail or stud as used by upholsterers. Normally found set in the crown of a watch.
A cabochon(from French "caboche") refers to a unfaceted, round or oval cut-form of semi-precious stones, which is flat at the bottom and arched at the top. Ground jewels like this are sometimes embedded in the crown of wristwatches for decoration.
Is an additional gear mechanism used for repetitions, calendars or chronographs.
A calendar that not only shows the date but may also show the day of the week, the month, or even the year. Some calendar watches need to be adjusted manually whenever the month is less than 31 days long. Another type called perpetual calendars, are self-adjusting over several decades or even centuries.
A feature that shows the day of the month, and the day of the week. Some calendar watches show the date on a scale which is on the outside edge of the watch dial, while others use sub-dial.
See Annual Calendar
See Annual Calendar
See Perpetual Calendar
A watch featuring a complication showing the day / month / day / moonphase / year combinations. Perpetual calendar watches adjust automatically, while other calendar watches need to be adjusted manually every month.
See Movement.
A size or style of a movement is also known as a caliber. This is generally used by a manufacturer when denoting a specific model name for a movement.
See Watch Caliber
This is a dial which uses Roman numerals(10,11,1,2) and Arabic numerals (4,5,7,8), with the 3,6 and 9 often being indicated as dashes and the 12 being an inverted triangle.
A curved or arched dial or bezel.
An arched glass or window of a watch that makes it appear to be dome-like in appearance.
The cannon pinion is the heart of the motion works. This piece is what translates the movement of the wheels on the back into the time keeping display on the front. Most commonly (there are several exceptions) this is attached to the center wheel via friction fit and it is the post that the minute hand is set on.
No definition found
Unit of measure for gems based on weight. One carat is 0.2grams
Carbon fibers or carbon fibers are fibres about 5–10 micrometers in width and composed mainly of carbon atoms. Watches made out of carbon fiber are designed to be unaffected by physical abuse and display increased resistance against corrosion, heat, and other elements.
The carriage consists of an upper bridge and lower bridge, made from steel plates and separated by two pillars. The escapement and balance are mounted within these plates.
This is the center section of the watch case excluding the back and the bezel
This was a line of rectangular watches produced and designed by Cartier inspired by World War I tanks.
The metal housing containing the watch movement. Usually made of precious or base metals but can also be made from carbon composite, plastic, rubber, ceramic and other materials. They are various shapes such as round, square, rectangular, barrel, oval and more. This protects the inner workings and gives the watch its exterior appeal.
The reverse or back side of the casing which can be removed to access the inner workings. These are usually stainless steel or crystal (so you can see inside).
The case diameter is the measurement from one end of the case to the other and does not include the crown or buttons
When watchmakers design a watch, they use various styles and types of cases using precious metals, stainless steel, and other materials including plastic.
See Case (Watch Case)
The thickness is measured from the top of the crystal to the base of the case
A sweep seconds watch is one where the seconds hand axis is at the center of the dial.
These are also called Senter Seconds or sweep seconds. They are mounted on the centre post of the watch for better readability.
The center wheel is accurately named as it usually is in the center of the movement. It is driven by the barrel and oscillates once per hour.
Sweep seconds, also known ascentral seconds, is when the seconds hand is placed on the main dial along with the hour and minute hands. It does share the same path or track with the other hands. The hours, minutes and seconds all read from the same dial
Cerachrome is a ceramic material used to make the bezel inserts of the modern GMT, Submariner, Daytona and Yachtmaster II watches. It is almost completely resistant to scratches, and it's color is unaffected by the ultraviolet rays of the sun.
The ceramic material used in watches differs to the typical ceramic that comes to mind. Ceramic is commonly described as any material that is inorganic, nonmetallic and solid. Modern brands engineer ceramics using pure materials and compounds of metals to create the durable element found on the watch.
Treatment by hand of the dial or case surface. The pattern is created by hollowing a metal sheet with a engraver and subsequently filling the hollows with enamel.
The ring on the watch dial which is marked with the minute marks. The hour figures are also referred to as chapters.
Large marks on the chapter ring denoting hours. Quarter hours may also have their own chapters.
A bell like sound that is made when a clock strikes on the hour, half hour, quarter hour and minutes. The chime is alike to that found in a grandfather's clock.
A complication that permits a watch to act as a stopwatch with an accuracy down to a tenth or a hundredth of a second. Some styles allow for lap timing, as well for individual contestants in a race or events in a process.
A time that can be started and stopped to accurately time an event where an exact time period is required.
A type of watch that features an extra stopwatch function in addition to the main time. A chronograph can be either mechanical or quartz (or a combination of the two) and is activated through a set of pushers protruding from the side of the case. (See some of our favorite modern chronographs here.)
A rattrapante is a fly-back hand chronograph that enables the wearer to measure split-seconds or multiple events of varying durations.
A chronograph watch is defined as a timepiece that can be used as a stopwatch in addition to its standard display watch capabilities. Where as a chronograph watch will have dials that keep track of seconds, minutes and hours.
A precision timepiece that is capable of keeping time with a meticulousness and accuracy suitable for navigation. Swiss-made watches are certified as chronometers only by meeting the standards set by the Swiss Official Chronometer Control (COSC). The certification includes several days of rigorous testing under various pressures and temperatures. The sad thing is that a one dollar quartz watch can often out perform a very expensive luxury timepiece.
A watch that has been independently tested by the Official Swiss Chronometer Testing Institute (COSC) in Switzerland, (or any other official governing body in other countries). In the case of the COSC, watches are tested over a period of several days in six varying positions at three different temperatures. This is while remaining accurate to within -4/+6 seconds per day for mechanical watches and ±0.07 per day for quartz watches. (Learn more about chronometers here.)
An instrument for calculating time very accurately. Before a Swiss watch can be classified as a chronometer, it must meet very high standards set by the C.O.S.C. (Controle Officiel Suisse des Chronometers). The requirements are 15 days and nights at five various positions and different temperature changes.
A surface finish that is created through the application of abrasive to a workpiece while that workpiece is oscillating in a lathe. This method is often used for wheels.
Fastening contraption for straps and bracelets. Bands made of materials like leather, rubber, and cloth tend to use buckles. Bracelets and expensive leather straps use deployment straps for a tighter fit with less wear.
Enamel set in-between strips of metal and baked onto the dial of the watch.
Connected minute graduations that form a ring. These are also called continuous minute ring dials.
A distinct type of dial guilloche or embossing, resulting in small square knobs.
Computer Numerical Control - CNC machining is a manufacturing process in which pre-programmed computer software dictates the movement of factory tools and machinery. The process can be used to control a range of complex machinery.
See Co-Axial Escapement
The coaxial escapement is a version of modern watch escapement mechanism invented an by English watchmaker by the name of George Daniels. The coaxial escapement is a modification of the lever escapement with some features of the detent escapement. The critical virtue of the Daniels escapement is the virtual elimination of the sliding friction component; i.e., the sliding of the pallet stones over the teeth of the escape wheel. What little sliding friction remains is due to the impossibility of maintaining an exact tangential geometry throughout the duration of an impulse.
The elaborately engraved plate (usually of brass, sometimes gilded) which supports the balance-staff pivot and preserves the balance wheel
This is a red and black bezel insert on the Rolex GMT Masters. The colors are of the soft drink producers' (Coke) brand color scheme.
The upright, notched oscillating wheel in a chronograph that is used as a sliding link to operate the different levers that switch a chronograph on and off and return the chronograph hands to the zero position.
This is a shortening of Compagnie Maritime d'Expertise, which is a French diving company. Comex and Rolex worked together to design a one-way escape valve for the Rolex Sea-Dweller watch in the 1960s. The Rolex Comex was distributed internally only, making this a prized collectors piece.
A compass is an gadget used for navigation that shows direction related to the geographic cardinal directions (or points).
Can be called a "compensation balance". This is a very specific type of balance used mainly for meticulous watchmaking before the arrival of modern, Nivarox-type balance springs. Watches that were made before the 20th century used plain steel balance springs; these were prone to changes in elasticity as the temperature changed, which could badly disrupt the veracity of a watch. Watchmakers learned that if a balance was made of two strips of brass and steel laminated together, then two cuts made in the balance's perimeter, that the amount the balance changed in size as temperature changed, almost completely canceled out the change in the elasticity of the balance spring.
A complete calendar, sometimes called a “full calendar”, is a watch that displays the day of the week, the date, the month of the year and, of course, the time. Often these watches also show the phase of the moon. Considered the total calendared entry point or as a gateway watch to high complexities.
A watch complication is any action that exists in addition to telling time (displaying hours, minutes and seconds) on a timepiece. These watch complications allow special functions to be performed and displayed on the watch to enhance or simplify your life.
An extra function of a watch that goes past just telling the time, like a stopwatch (chronograph), calendar or a moonphase indicator. Complications require extra parts and make a watch more expensive and complex to build.
A multi-part mechanism that provides an extra horological function, providing more information than just the time. Complicated functions will include a minute repeater, tourbillon, perpetual calendar, split second chronograph and others.
The buckle is concealed under the links of the bracelet, given the watch a continuous look along the length of the bracelet.
A concentric circle starts from the center and radiates out to the edge, 3 dimensional circles expand from small to large.
A corrector is defined as a flush or inset button used to correct an internal complication in a watch, typically a calendar
The COSC is the Controle Officiel Suisse des Chronometre which is the only authoritative chronometer testing organization in Switzerland.
A chronometer created and named by Rolex that has a tachymeter seated on the bezel instead of the dial.
The Cotes Circulaires are, in the watch industry, a type of finishing decoration of the movement of the watch. These decorations are characterized by a pattern of circles at regular intervals that have been performed using an abrasive tool.
Also known as damaskeening, this is a pattern of regular strokes running parallel to give a ribbed or wavelike appearance on parts of the watch such as the bridges.
Time that remains in a predefined period.
A complication that counts down in reverse from a time that's been preset for example, timing an egg or a parking meter. This can include an audible alarm to alert the wearer when the time has passed by. This is usually found on quartz watches.
An extra hand on a chronograph that indicates the time elapsed since the beginning of the measuring. On more modern watches, the second counter is placed in the center, while the hour and minute counters have off-centered hands in special zones, also referred to as subdials.
Aftermarket parts bearing non-authentic trademarks, hallmarks or logos used to make the parts appear genuine.
Illegal copies of watches, often branded to appear original, and usually sold as authentic.
Two protrusions on either side of the crown on the watch case to mitigate damage to the crown.
See Chronometer
A button is on the side of the case that pulls or screws out. This allows the wearer to adjust the time and date or synchronize the seconds. In non-automatic watches, it is also used to wind the mainspring. Screw-in or screw-down crowns or similar mechanisms seal the watch to waterproof the watch and to keep out water at extreme depths.
A button that is often fluted that is found on the outside of the watch case that is used to wind the mainspring in mechanical watches. The crown is also used to set the time, when pulled out, and for setting a watch calendar. A screw-down crown is used to help make the watch more water resistant and to help keep out dust.
A crown can be described as a small knob on the side of the watch case that can be used to adjust the time and dat. If your mechanical watch isn’t automatic, the crown must get wind to keep the watch running.
Wheel meshing with the winding pinion with the ratchet wheel on the barrel-arbor
A translucent cover that protects the watch dial. Crystals can be made of either glass, plastic or synthetic sapphire. Non-reflective coatings are applied on some crystals to prevent glare. (See also: Mineral Crystals, Plastic Crystals, Sapphire Crystals)
A transparent cover over the dial or in the case back, or it may make up the entire case. The crystal ordinary glass, mineral glass, acrylic plastic, synthetic sapphire, or ruby. Sapphire is favored for high-end watches since it's almost as hard as diamond, although a few use plastic because it's easy to repair and cracks instead of shattering into small, potentially dangerous fragments.
The see-though protective cover that protects the watch face, made from either synthetic sapphire, acrylic or glass. Synthetic sapphire is the most pricey to produce, however, it is considerably more scratch resistant than acrylic or glass crystals.
Is when the back of the watch has a window made of clear crystal that shows the craftsmanship and design of the working movement.
A square shape with rounded edges
Usually one of a kind. A custom made item made to someone's specific requirements.
A dust cover which is found on some cases.
A blister or lens that is created on a crystal to magnify a specific area, usually the date, making it easier to read.
COSC - Controle Officiel Suisse Chronometres is a company who tests timepieces.
The company did extremely well and their most famous and loyal customer was French Emperor, Napoleon III. The emperor, officially gave owner of the company, Francois Czapek, the title "Horloger de la Cour Imperiale." Meaning, Watchmaker to the Imperial Court.
This is the nickname used for the hollow jubilee link.
An alarm which is set to activate at a specific time every day.
An art of creating a pattern, design or wave feature on a watch.
Specific day and month related to a calendar year
Watches that have a complete calendar (Day, Date, Month) regularly have a Date Corrector so that you can match the date with the correct day. Often with a pusher at the side of the watch.
The mechanism which changes the date on a watch display on a daily basis.
A watch complication that shows Monday to Sunday as well as showing the date.
A watch with a Day/Date Function Complication.
A colored indicator on a dual or world time watch that displays if the home and second time zones are in daylight or night. It's particularly effective for watches without a 24-hour readout.
A shaded or colored band on a world time watch, that shows the time zones that are in daylight and those in darkness.
Shows the day of the week as well as the numerical date of the month
A deadbeat seconds, can also be called dead seconds or jumping seconds, is a mechanical watch in which the seconds hand ticks once a second, like any economical, run of the mill quartz watch.
In the world of watches, finishing describes the decoration of a movement. ... A large portion of mechanical movements have some form of decoration or finishing. It ranges from the simple, machine-performed engraving on rotors, to hand-engraved balance bridges. Many mechanical movements have some kind of decoration or finishing. A few only have an engraved rotor, others may beautiful decorations solely on visible parts, while others still are completely hand-finished, even the parts you can’t see through the display back.
Is a buckle that gets fastened to the watch strap that uses hinged extenders to open and closes the strap. This was invented by Louis Cartier in 1910. A deployant buckle is simpler to put on and remove than a tang buckle. The word deployant comes from the verb “deployer” which means to unfold. Do not erroneously refer to it as a “deployment” clasp. This safety feature also makes sure the watch won’t drop when putting it on your wrist.
A type of watch strap buckle that closes by folding in on itself, then clasping. Makes the strap simpler to take on and off and also keeps the leather from wearing or stretched out.
A deployment buckle, also commonly known as a foldover, is a tri-folding clasp that secures the two ends of the bracelet while allowing enough space to put the watch onto your wrist when opened.
A deployment clasp, known by many names for example a deployant clasp, a butterfly clasp or deployment buckle, or an invisible double locking clasp that is a broadening metal mechanism designed to close a watch band with a fitted look.
A buckle that permits a strap or bracelet to stay in one piece by opening and fastening using a hinged plate with adjustable extenders. The latter are very popular with divers or aviators, who may need to adapt the band to go over a wetsuit or jacket.
A type of buckle that hinges close and expands to slide over your wrist when opened.
Found on many diving watches, this alarm sounds or vibrates when the diver passes a preset depth.
A feature found on specifically diving watches. This sensor monitors the divers depth using water pressure. It will show the reading on an scale or digitally depending on the watch.
In Italian, Destro means to “right”. It means that the watch is intended to be worn on the right hand, and is most commonly identified for use with Panerai timepieces.
The detent escapement utilizes a very thin blade spring with a jewel seated on it to hold the escape wheel in place; a jewel on the balance trips the spring as it passes through, which releases the escape wheel, allowing it to advance. The escape wheel then gives an impulse directly to the balance, and is locked again as the blade spring falls back into place.
A disc, with a metal base and is visible through a crystal that carries certain indication, such as the hours, minutes and sometimes seconds.
Also referred to as the face, the dial shows the time, features numerals as well as the hands.
The upper side of the watch, which carries the hands, marks, indicators, and subdials. A dial may be simplistic, highly decorated, or divided into bridges to make the movement visible. .
Developed in the 1970s, digital watches use Arabic numbers in an LCD type display.
First developed in the 1970s, digital watches bypass the standard hands for easy to see Arabic digits that display in a liquid crystal screen. The digital display are often found in children’s watches, sport watches and computer watches. They are set and operated using different buttons located on the side of the case.
A watch that shows the date or time and other information via a digital display instead of hands. Digital watches are associated with quartz watches which were first marketed in the 1970s, using LED and LCD displays. Mechanical digital watches go back to the 19th century and have appeared from time to time as novelty items. It was largely believed in the 1970's and 80's that digital watches would not only push out analogue ones, but analog timekeeping as well. However, recent decades have seen a reappearance of analogue watches with digital watches going back to the cheaper or most specialized markets.
A watch that shows the time through a numerical, instead of ananalog display.
An analog watch (American) or analogue watch (UK and Commonwealth) is a watch which display is not digital but rather analog with a traditional clock face. The name is an example of a retronym; it was coined to differentiate between analog watches, which had simply been called "watches", from newer digital watches
See Damaskeening
This refers to the slight jerky forward movement of a seconds-hand on a watch.
Indication of time, date or other data, either by means of hands moving over a dial (analogue display) or by means of numerals appearing in one or more windows (digital or numerical display); these numbers may be completed by alphabetical indications (alphanumerical display) or by signs of any other type. Example: 12.05 MO 12.3 = 12 hours, 5 minutes, Monday 12th March. Such displays can be achieved by mechanical or electronic means.
A dive watch is a water-resistant watch, however, not all water-resistant watches are necessarily dive watches. True dive watches must meet a specific standard for diving like ISO 6425. The standard requires the watch to be water-resistant to at least 200 meters, feature a unidirectional oscillating bezel and some form of illumination.
Also called a diver or dive watch. A watch with a case developed to remain water resistant to depths of at least 200 m (660 ft). It includes a dial created to be legible at a glance under bad light conditions, and may have an elapsed time bezel for timing decompression stops. Wrist dive computers are preferred by most divers, however most still wear a dive watch as a back-up.
A divers clasp is a type of deployment clasp with a fold over closure on top that provides extra protection.
For a wrist with a 200 mm (7.9 in) circumference wearing a 4 mm (0.16 in) thick diving suit sleeve increases the strap or bracelet length required the fit the watch over a wrist , with a sleeve onto 225 mm (8.9 in). For this bracelets often have a hidden divers extension deployant clasp by which the bracelet can be appropriately extended by approximately 20 mm (0.79 in) to 30 mm (1.2 in). Some watchstraps allow an increase in length by adding a diving suit extension strap piece to the standard watchstrap. If needed, more than one diving suit extension strap piece can be added to the standard watchstrap.
It's function is actually quite simple, before a diver’s descent, the 12 o’clock bezel marker is aligned with the minute hand, allowing the elapsed time, up to 60 minutes, to be viewed on the bezel. Which is the reason why quite a few dive watches come with a particularly prominent minute hand. A unidirectional, ratcheting construction makes sure that – if the bezel is moved in error– the time already spent underwater would be measured as longer than actually spent, providing the diver with a safety reserve for the now more imminent ascent. The bezel/ minute hand combination does not, however, directly indicate how much air remains in the air tank.
A diver’s watch is designed specifically for underwater diving and will have a water resistance of approximately 200 to 300 m (660 to 980 ft). Dive watches have a unidirectional rotating bezel with 15 or 20 minute markings, a screw-in crown and backplate. Metal bracelets or rubber straps are used as they are sufficiently water (pressure) resistant and are able to endure the galvanic corrosiveness of seawater. Bracelets are often equipped with a divers extension deployment clasp by which the bracelet can be extended by approximately 20 mm to fit over a wetsuit. Dive watches generally have a relatively thick sapphire crystal to boost the pressure-resistance of the watch. Some watches which are intended for diving at great depths are fitted with a helium release or helium escape valve to prevent the crystal from being pushed off by an build-up internally, of helium pressure seeping into the watch case. This can happen when decompression stops during resurfacing are not long enough and a pressure difference builds up between the helium in the watch and the environment.
Is a watch created for underwater diving that features a water resistance greater than 1.0MPa (10 atm), the equivalent of 100 m (330 ft). Also known as a dive or diver's watch, the typical watch has a water resistance of about 200 to 300 m (660 to 980 ft), via modern technology permit the creation of diving watches that can go much greater depth. A true new-age diver's watch is in line with the ISO 6425 std, which characterizes test standards and features for watches suitable for diving together with underwater breathing apparatus in depths of 100 m (330 ft) or more. Watches in line with ISO 6425 are marked with the word DIVER'S to distinguish ISO 6425 conforming diving watches from watches that may be suitable for actual scuba diving.
A watch that is water resistant to a minimum of 300 Meter (30 ATM). It also has a one way rotating bezel and a screw-on crown and back. Has a choice of metal or rubber strap only. Has a sapphire crystal and if required, a wet-suit extension.
DLC coated watches are completely impervious to scratches. A DLC coating is considered the best quality PVD coating because it is the most durable and the hardest to scratch. The DLC coating adds a coating on the watch which also protects it against elements of regular wear.
A watch that is tough, easy to keep sterile, clean, and has a special seconds hand and special markings to allow a doctor to quickly measure a patient's pulse.
A water-resistant watch that is recommended to use for swimming, snorkeling, boating and other water sports.
Concave shaped glass
Crystals with a concave appearance. Double domed with have a concave appearance on both sides.
A Double named watch will have more than one company name on the dial such as that of the manufacturer and the retailer.
This is a feature that allows for the day and date to be set quickly by turning the crown as opposed to turning the hands over and over.
Double Swiss refers to the printing of the word SWISS at the 6 position. The lower printing is usually not visible in it's entirety until the face is removed from the case.
NO DEFINITION FOUND
A watch that is able to display the time in two different time zones simultaneously.
Measures both a selected current local time and at least one other time zone. This can be found in a twin dial, extra hand or subdial and can be referred to as world time.
A useful complication for those who like to travel or have family located in different time zones. This measures both the current local time and at least one other time zone. Some watches such as the Rolex GMT Master II can even track three times at once, see GMT below]. This can be found in a second dial, an extra hand, or in a subdial. Dual time may be referred to as a world time function.
A dual time zone bezel is a oscillating bezel that can be used to show another time zone separate from the dial
Dual Time watches are essentially pretty self explanatory—they show two different times, at the same time. Most often you’ll see a subdial somewhere on it's main dial indicating the second time (most often hours and minutes, and other times strictly hours) on a 12-hour scale. GMT watches rely on a 24h format for time indication. The most commonplace examples will display a second time zone using a central hand and a 24h track either running along the dial, the rehaut, or the bezel, which can either be fixed or rotatable. The GMT watches with a moving bezel add an extra layer of practicality so long as you don't mind a little math.
A dual time/second time zone contains a revolving bezel, which can be used to show a separate time zone distinct from that shown on the dial.
A watch that measures your current local time as well as one other time zone. The added time element may originate from a twin dial, extra hand, subdials, or some other means.
This is a display in analog (hour and minute shown on the dial by hands) and digitally (display in numbers). Another phrase for this display is AnaDigi, a portmanteau word derived by joining together the first syllables of Analog and Digital.
A watch that has two movements and not just one. This is particularly useful to keep accurate time in two different time zones when travelling.
Means Of Life. This is an indicator on quartz watches that displays that the battery is almost spent and needs replacing.
Pointed crown guards which look similar to the beak of an eagle.
An ebauche is a watch movement that is built with the intent of being put together into a watch casing somewhere else. Watch companies outside of Switzerland regularly utilize Swiss movements that are shipped and then assembled together in factories elsewhere in the world. Quite often each part of the watch is made separately in order to save money. Consumers should be very cautious of buying an ebauche timepiece and should take the time to research the watch before making a purchase.
French term for “sketch”. In a watchmaker’s environment, the movement blank of a watch is described as an “ébauche.” A functional movement is made up of a movement blank, an escapement, a hoop-shaped balance and it's spiral shaped coiled balance spring, a mainspring, a dial, and hands. An ébauche is a entire movement (plates, bridges, gear train, steel components) except for an escapement, balance, balance spring, mainspring, dial, and hands. Depending on the requirements of its recipient, ébauches are available either with or without pressed-in jewels. The French word chablon, for which there is no English equivalent, is occasionally used in the description of movement blanks. A chablon consists of unassembled components for an complete caliber or for different parts of a caliber. Blank movements are created and built by specialized companies (e.g. Eta, Nouvelle Lémania, Frédéric Piguet).
See Ebauche
Is a name for a patented power mechanism that is found on some Citizen watches. These mechanisms utilize ordinary light to keep a rechargeable battery powered for watch operation. This technology is very refined thus allowing some watch models to remain powered for up to 5 years in the dark. Watches that are built with Eco-Drive technology will never need to have the battery replaced.
A movement that has been specially constructed, needs to be wound just once a week. In one eight-day movement, specifically used in the Hebdomas wristwatch that was introduced around 1913, the barrel covered the movement’s entire surface. In the 1930's Eight-day shaped movements had normal size barrels, however, each movement had two extra wheels added to it's train. Eight-day movements are commonly found in pendulum clocks and other larger timepieces.
Elapsed time refers to the actual time it takes for an object to move over a specific distance.
An elapsed bezel is a graduated rotating bezel that can keep records of sections of time. The bezel is turned to align the zero marker with the watch’s minute or seconds hand. The time that has elapsed can then be read off the bezel, rather than the wearer having to perform maths and subtract time.
A bezel that is rotated for tracking elapsed time by lining up the zero mark with the minute hand, so the result can be read correctly.
A watch that runs on an electric current instead of the normal mechanical movement. This in general refers to a quartz movement, but can be used in regards to watches that use tuning forks or other electric or electronic regulators.
Also known as a quartz watch, it has a battery powered or energy generated movement, which utilizes an electric current to start a quartz oscillator to vibrate at 32,768Hz per second. These vibrations are then handled by a circuit that changes the current into an impulse which feeds a stepping motor and drives the gear train. Some quartz watches have solar cells which transform natural and artificial light into energy.
Electronic watch may refer to: Electric watch - Pre-quartz watches that were powered electronically
Electroplating is a process of covering metal items with a film of other metals. The item is put in a chemical solution; electric current (D.C.) flows through the solution via a piece of metal (anode) to the article (cathode), adhering the metal thereon by electrolysis. See also PVD.
An elinvar is a type of hairspring that’s made from a mixture of metals that are specifically designed to be unaffected to changes in temperature and to be more accurate in varying elements.
Decorated with or having the form of a raised pattern, design or image.
“Émail” is the French word for “enamel”, a vitrifiable liquid which can be given different colors and fused onto the surface of metals, either to protect or decorate the substrate. Enamel is made up of silicious sand and calcium fluoride to which lead oxide, borax and soda are added. The mixture is first melted at 1,200 degrees Celsius, then goes through a process called flash cooling. The granules that result from this process are ground to a powder together, then coloring agents, which include: antimonies, zirconium oxide, or titanium dioxide for white enamel; cobalt oxide, chrome oxide, or other colorants for colored enamel are added. The layers of enamel are either brushed or sprayed onto the metal substrate that has been cleansed, or the entire metal piece can be dipped into the enamel. Afterwards the coated piece is fired in a special kiln at a temperature of between 800 and 900 degrees Celsius. The enameling technique has been used for more than 350years on the dials and cases of the watches. During the first couple of decades of the 20th century, enameled dials were virtually standard equipment on fine wristwatches. This is partly because of the expenses involved in their manufacture, enamel dials have become quite rare during the past few decades.
End Of Life. This is a symbol on quartz watches that displays that the battery has almost expired and needs to be replaced.
This is a small section of metal which is made to look like a link of a bracelet, which allows the bracelet section to be attached to the case with very small spring bars.
End shake is caused when a jewel hole is worn out causing an arbor to shake.
See EOL
Undrilled jewel, fitted on the balance jewel with the tip of the balance-staff pivot reclining against its flat surface, to lessen pivot friction. Occasionally for used pallet staffs and escape wheels.
Is an undrilled jewel, that is domed on one side flat on the other. The flat side of the endstone is placed on the balance jewel to limit the vertical play of the balance staff. The bearings for balance staffs are normally equipped with endstones. In very good quality calibers, endstones can also be used for the bearings of the pallet staffs and escape wheels.
The ability to accomplish work. Potential energy is essential to power the gear train of a watch. In a mechanical clock, the source of this energy can come from a tightened mainspring (spring power) or a weight that's been raised (gravity power). The electrical energy needed by a quartz timepiece can be supplied by a battery, a capacitor or an accumulator.
An engine-turned watch is a process of using superannuated machinery to engrave intricate patterns on metal parts of the watch which including dials, cases, bezels and the actual movement. Today, this technique is often referred to as “Guilloche”.
Decorative engraving, usually on the watch face.
A surface adornment typically applied to the dial and the rotor using a grooving tool with a sharp tip, such as a rose engine, to cut an even pattern onto a flat, even surface.
See End of Life
Due to the elliptical shape of the Earth’s orbit around the sun and because of the tilt of the Earth’s axis, the difference between the year’s shortest and longest solar days amounts to 30 hours and 45 seconds. Keeping time according to true solar time with its continuously changing day lengths would be impractical in daily life, so astronomers defined “mean solar time”. The length of a mean solar day (86,400 seconds), which is indicated by all ordinary clocks and watches, is calculated by averaging the lengths of all of the true solar days in one year. The equation display, which was invented in the late 17th century and which has since become extremely rare, depicts the difference between mean solar time and the true solar time. The maximal deviations occur in mid February (+14 min. 24 sec.) and early November (-16 min. 21 sec.). The lengths of the true and mean solar days are identical four times each year (on April 16, June 14, September 1, and December 25). The daily differences are programmed into the circumference of a kidney-shaped cam that annually completes one rotation around its own axis. An elaborate mechanism “reads” this cam and transfers the information to an additional minute hand or second pair of hands on the dial’s equation display.
A complication that shows the differences between true solar time and mean solar time. The Equation of time complication shows by how much the two times deviate from one another on a particular day.
An Equation Of Time or EOT is a complication that shows the difference between true solar time in nature and mean solar time in man. As the earth revolves around the sun in an elliptical shape and the axis is tilted – there are only 4 days a year when the day is precisely twenty four hours long – April 15th, June 14th, September 1st and December 24th. Every other day of the year, the days are either slightly shorter or longer, depending on the position of the earth. The EOT complication showcases the contrast between the “mean” and “true” time.
The escape wheel is just one part of the device recognized as the escapement. The club-shaped teeth on the escape wheel connect with the pallet fork to translate spinning motion into lateral impulses.
A device in a mechanical watch that controls the movement of the hands by controlling wheel rotation
Is an internal component in a mechanical watch that moves the power from a wound-up watch into the movement of the watch’s seconds hand by driving the balance wheel at a constant rate. A vast majority of modern watches use a “lever escapement,” comprising of an escape wheel and a lever with two pallets. The escape wheel is attached to the gear train (which receives energy from the mainspring), the lever, pallets lock and unlock the escape wheel at a constant rate. This component is what causes the watch’s ticking noise.
The piece of the watch movement that divides the time into a series of beats or oscillations. There are so many variants of the escapement that they could fill a museum.
The most prominent manufacturer in Switzerland for movements used in many Swiss brands.
The French term “établisseur”, for which there is no English equivalent, stands for a watchmaker who buys components (movements, dials, hands, cases, etc.) from specialized manufacturers, then further processes and assembles these components to produce complete timepieces.
Etching goes through a process of utilizing a strong acid or mordant to carve into the unprotected pieces of the metal surface to create a design in the metal. In traditional pure etching, Normally metals like copper, zinc or steel plate is covered with a waxy ground which is resistant to acid.
See Perpetual Calendar
Exclamation Point refers to a phosphorus marker which looks like the punctuation exclamation point. This is usually positioned above the 6 index. Many gilt dials from the 1960s featured this.
Also called and "open" case back, this is a see-through cover on the rear side of a watch case that shows off the inner workings of the movement. The same as skeletal case back, the purpose is to showcase the movement though a crystal that's place on the rear of the case.
Fuerza Aerea del Peru or Perucian Airforce. Rolex supplied watches made especially for FAP which are engraved on the caseback and have serial numbers inside the caseback. These are very rare timepieces and sought after by collectors.
See Dial.
The steel and brass pieces of very fine watches have faceted edges (chamfering). The bevels on the edge of the piece should ideally form a 45° angle.
Within the Swiss watch industry, the phrase manufacture is used for a factory where watches are manufactured almost entirely. This can be distinguished from an "atelier de terminage", which only deals with assembling, timing, fitting the hands and casing.
Together with the insignias which spell out their names, quite a few watch companies and ébauche makers also used and continue to use a so-called “factory mark”. This mark, a easily recognizable logo, can be placed onto different locations on a watch movement. It is frequently found on the front side of the plate in a location which is ordinarily covered by the dial. Manufacturers of movement blanks occasionally place their factory marks (along with the caliber number) underneath the balance near the balance cock. Cases usually bear the factory mark on the inside of the back. A few manufacturers memorialize their logos on the outside of the watch, e.g. on the crown, back, and/or dial.
A watch designed to be issued to soldiers originally ,for use on the battlefield. They are notable by their simplistic, rugged, and easy to service construction.
A mechanism used to make very small alterations in the position of the index (or regulator). A large number of various constructions can be used to accomplish fine adjustment in mechanical watch movements. Swan’s neck fine adjustment is among the most exclusive of such mechanisms. A system which relies on an eccentric screw is far more common. A widely held but erroneous belief insists that a fine adjustment mechanism necessarily goes hand in hand with greater precision. Watches can be adjusted with a high degree of exactness simply by carefully positioning the ordinary tail of the index, although this operation requires extreme care and dexterity.
Exact adjustment of a watch’s rate by way of a device such as a swan’s neck regulator or eccentric screw.
The eradication of as many factors as possible which may exert negative effects on the rate of a watch or clock. The degree of fine regulation depends upon the standards of the timepiece’s manufacturer and therefore have an effect on the price of the finished product.
The ratio between the weight of the precious metal (e.g. platinum, gold, or silver) in an alloy and the total weight of the alloy. Nowadays, fineness is asserted in thousandths or in carats. Pure gold is 1,000/1,000 or 24 carats. The value of a carat amounts to 1/24th of the total weight: 1,000 divided by 24 equals 41.666. Fourteen carats thus corresponds to 585/1,000. Eighteen carats corresponds to 750/1,000.
The final work of assembling the parts of a watch and putting its case into working order.
Fishermen & Hunters have used the phases of the moon to anticipate the best time for fishing/hunting. These watches show moon age; time to fish/hunt, and sunrise/sunset based on set Latitude and Longitude.
Christian Huygens invented the flat balance spring in 1675. The spring’s points of attachment to the balance staff (collet) and balance cock (stud) both lie in the same plane as the spring itself. Not like the Breguet overcoil balance springs, flat balance springs have the disadvantage that they do not develop precisely concentrically while they expand and contract. This can have a negative effect on the rate results. Modern mechanical movements usually have flat balance springs which have been given a special deformation to counteract the aforementioned shortcomings
Flinque is described as the engraving on a dial or the case of a watch, covered with an enamel layer.
Said of surfaces worked with thin parallel grooves, chiefly on dials or case bezels.
On chronographs, the flyback hand is used to record time that has elapsed, and restarts the instant it is reset to zero without the need to stop and start the watch again. It's notably useful when repeatedly timing a series of events
A hand on watches and particularly chronographs that immediately jumps back to zero. On a normal watch, it can be used to preserve space on the dial by including a minute or second hand travel along an arc instead of revolving around the whole dial. When it reaches the end, it jumps back to zero in an instant.
A type of chronograph that can be reset without halting the chronograph function (which is necessary in a normal chronograph). It is especially useful among pilots and other users who need to record multiple times in quick succession. (Learn more about chronographs here.)
A fly-back is a chronograph that restarts automatically the moment it is brought back to zero. Particularly useful to aviators, it allows the pilot to continue usage without having to stop, reset and start the chronograph over again.
In a chronograph watch, there is a supplementary seconds hand that moves concurrently with the standard seconds hand. The supplementary hand can be stopped independently, then made to catch up (“fly-back”) with the other seconds hand that is continuously moving.
The flyback hand is a second hand on a chronograph that is used to time several events of many different times. It was given the name “fly back” due to how quickly it can jump back to the zero marker after reset.
A fob is nothing more than a chain often present on pocket watches.
An Oyster bracelet with a folded link visible on the side. This is a Rolex design.
Global Watchband carries only deployment buckle fold over clasps that feature a pressure snap flip lock design to keep it fastened securely. Using these fold over buckles on any regular strap will extend the life of the band because it is not being pulled through a buckle.
Fold over clasps are normally brass and are connected to a necklace or bracelet by crimping the end to a jump ring. A fold over clasp collapses on itself and locks with a pressure tab.
The fork is part of the pallet fork and arbor which looks very much alike to a pitch fork and is used to make contact and engage the roller jewel on the balance.
Spare parts made by the original manufacturer of the watch, after the watch is no longer produced are known as fornitura. They may not be exactly the same the original parts.
A foudroyante is a sub-dial showing fractions of a second. This complication can also known as the flying seconds hand.
The fourth wheel rotates once per minute. In movements that display seconds in a sub-dial, the seconds hand is attached directly to the extended fourth wheel pivot on the dial side.
Number of oscillations per unit of time, expressed in hertz (Hz). Most stationary clocks primarily rely on a pendulum as their rate-regulating organ. Portable timepieces are typically equipped with a balance. Both organs oscillate at a particular frequency. The pendulum of a seconds-pendulum clock requires exactly one second to complete the arc from one turning point to the other, so it has a frequency of 0.5 Hz or 1,800 beats per hour (A/h). Early balances increased the frequency of oscillation to 7,200 or 9,000 beats per hour. The frequency of the balances of pocket watches was first raised to 12,600 and later to the typical standard of 18,000 beats per hour (2.5 Hz). In wristwatches, this latter too, balance frequency became the norm. To enhance precision, some watch manufacturers further increased the balance´s frequency to 21,600 A/h (3 Hz), 28,800 A/h (4 Hz) or even 36,000 A/h (5 Hz). However, balances that oscillate at higher frequencies also require more energy than slower-paced balances. Furthermore, as rotation speeds and centrifugal forces increase, considerable lubrication-related problems arise. Modern quartz clocks oscillate at a frequency of 32,768 Hz.
The speed at which a watch ticks (or beats), that is measured in either vibrations per hour or hertz. The majority of modern, high-end mechanical watches beat at a frequency of 28,800 VpH (4Hz). Watches that beat at 36,000 VpH (5Hz) or higher are called high-beat watches. A watch’s frequency is regulated by the oscillations of its balance wheel.
A complete calendar with displays for the day, date, and month. Manual resetting of the date and month display is necessary at the end of months which have fewer than 31 days. Some wristwatches with full calendars automatically advance the month display at or near midnight on the day when the date display has reached the number “31”.
A blanket term for the things that a watch can do. The term is not the same as a complication, as functions can include basic timekeeping. Also referred to as complications, functions are the various tools and tasks that are able to be used on the watch
An archaic way of equalizing the power of a mainspring as a watch unwinds by using a chain wound around a spiral-grooved, truncated cone. As the watch winds down, the chain is unwound from the narrow top of the cone and onto the mainspring barrel. As a result the mainspring has less force as it unwinds, the chain sitting in progressively wider grooves of the spiral compensates and the watch runs properly.
See Helium escape valve
A gasket can be made of rubber, neoprene or plastic ring used to seal the gaps between the case and the case back, crystal and crown to prevent water or dust from coming in the case and damaging the movement inside.
A gasket is a rubber ring set in the back of a watch case, crown, or crystal to protect against water and dust. Incorrect replacement while servicing can ruin your whole day.
A vast majority water-resistant watches are fitted with gaskets to seal the case-back, crystal and crown from water infiltration. Gaskets must be checked every couple of years to maintain water resistance
A centimeter / gram / second electromagnetic unit of magnetic flux density. This measurement was named after physicist Karl Gauss. The Rolex Milgauss references this measurement as it can withstand a 1 thousand gauss magnetic flux density. Thousand is mille in Latin.
A system of gears that relay the power from the mainspring to the escapement.
A system of gears that take the power from the mainspring to the escapement.
In a normal hand-wound watch, the gear train consists of five pairs of wheels with their accompanying pinions. The teeth along the periphery of the barrel mesh with the leaves of the center wheel’s pinion, which is affixed to the same staff that bears the center wheel. The center wheel’s teeth mesh with the leaves of the pinion of the third wheel. The third-wheel meshes with the pinion of the fourth wheel. The fourth wheel meshes with the pinion of the escape wheel. Energy flows through the escape wheel and the other parts of the escapement system, ultimately arriving at the balance, which is thereby kept in motion.
The series of gears of a watch movement that goes between the mainspring and the display or a complication. The arrangement manages the running of the watch.
The way a Quartz watch work is very contrasting to the way to pendulum clocks and ordinary watches. They still have gears inside to count the seconds, minutes, and hours and move the hands around the clock face. But the gears are controlled by a tiny crystal of quartz rather than that of a swinging pendulum or a moving balance wheel.
A law passed on December 6, 1886 to regulate the voluntary monitoring of pocket watches forms the legal basis for the so-called “Geneva Quality Hallmark” or “Poinçon de Genève”. It stipulated strict standards of quality for the manufacture of watches in the Canton of Geneva. This regulation was made considerably more rigorous in 1957. From that year onwards, watchmakers who wanted their watches to bear the coveted hallmark were required to uphold 11 quality standards. The accuracy of a watch´s rate also occupied the focal point of interest. Wristwatches with movements measuring 30 mm or less in diameter had to undergo an 18-day testing program. Only if the movement fulfilled all of the criteria did it qualify to bear the “Poinçon de Genève”. The most recent version of the regulation dates from December 22, 1994. Preconditions for receiving the Geneva Quality Hallmark are the numbering and the submission of all candidate movements to the “Office for the Voluntary Monitoring of Geneva Watches”. The principal contents of the regulations involve the determination of twelve criteria related to the level of quality of all components and their processing. Among other details, steel parts must have polished edges and satin-finished front surfaces. The heads of screws must be polished or circularly grained; the slits in the screws’ heads must be chamfered. Other stipulations specify details about the jewels, gears, arbors and pivots, the affixing of the balance spring to the balance cock, the technical execution of the all-important oscillating and escapement system, the care taken in the crafting of the winding and hand-setting organs, and the labor which must be devoted to the making of the movement’s other components. Unlike the text of the 1957 law, the current regulations no longer stipulate minimum standards for the precision of the rate of submitted movements. Then as now, however, candidates for the Geneva Quality Hallmark must be assembled and adjusted within the territory of the Canton of Geneva.
Also known as the "Poinçon de Genève." The authoritative seal of the City and Canton of Geneva, Switzerland. In horology, it's used as a seal of quality assurance by the Watchmaking School of Geneva on watches made in the Canton that have been submitted for and passed a special inspection. This is established on 12 criteria regarding the movement's materials and finishing.
A commonly seen, rib-shaped embellishment given above all to the bridges and cocks of fine calibers. Geneva waves are activated before the components are galvanically ennobled, but stay visible even after that treatment. Geneva waves are typically found only on high-quality movements.
Also known as "Geneva stripes" or "côtes de Genève." These are adornments consisting of stripes applied to a watch's plates, bridges, balance cocks or rotors.
Famous wave-like fanciful pattern created on the bridges and oscillating weights of Patek Philippe watches. The tool required is crafted from boxwood by the craftsman, coated in abrasive paste, and then pressed manually in order to remove and extremely small amount of material and emboss the design.
Unique alloy composed of copper, zinc, & 10% nickel. The nickel reduces the oxidation of German silver and therefore eliminates the need to electroplate, and remain “untreated”
Unique alloy composed of copper, zinc, & 10% nickel. The nickel reduces the oxidation of German silver and therefore eliminates the need to electroplate, and remain “untreated”
See Gilt Dial
A gilt dial is when the lettering on the dial is golden in color rather than white. This is found on the older 5513 and 1675 (as well as others). This is very rare.
Thin plate of glass or transparent fabricated material, for the protection of the dials of watches, clocks, etc.
Bronze and beryllium alloy used for high-quality balances. This alloy ensures high elasticity and hardness values. It is non-magnetic, rustproof and has a very diminished dilatation coefficient, which makes the balance very stable and ensures high accuracy of the movement
The glucydur balance is a modern balance which replaces bimetallic compensating balances in high quality watches after the invention of the compensating balance spring. Glucydur balances consists of a copper alloy which contains an admixture of approximately 3% beryllium. Glucydur can be identified by its golden color. The simpler nickel balances on the other hand, have a silvery hue. Glucydur balances have a hardness level of 380 Vickers, nickel balances have a hardness level of 220 Vickers; brass balances have a hardness level of 180 Vickers. The greater hardness of glucydur balances makes them better suited for riveting, poising, and fine adjustment.
Even though it stands for Greenwich Mean Time, a watch referred to as a GMT has the ability to track two different time zones at once. Originally manufactured by Rolex for pilots in the ’50s, they are very useful for any frequent flyer. (See some of our favorite GMT watches here.)
Greenwich Mean Time. Synonyms are either World Time or Universal Time Coordinate (UTC). The prime meridian, i.e. zero degrees longitude, goes from north to south through the center of the GMT time zone. The mean time at the observatory in Greenwich, England is used as the standard for navigational purposes and international radio communications.
Greenwich Mean Time (GMT) is the time at the Prime or Zero Meridian that goes through the Royal Observatory in Greenwich, England and does not have summer time or daylight savings time. It is often mixed up with Coordinated Universal Time (UTC), but the second is actually a specifically determined scientific time standard, which is continually adjusted to remain in step with time as it is noted by an atomic clock.
Greenwich Mean Time is based on the globe being split into 24 time zones as established in the London Meridian Conference of 1884. The zero meridian goes through the Royal Observatory in the London suburb of Greenwich. In contemporary watch terminology, GMT is often used to describe a wristwatch that displays a second time zone or a 24hour indication.
See GMT
Also known as Greenwich Mean Time, it is the international standard of time that the world's time adhere to. Every time zone is set against GMT. In watches, a GMT reference refers to the ability to show dual time zones with a second hour hand, primarily found in a 24-hour mode to determine day from night.
GMT or Greenwich Mean Time is also referred to as UTC (Universal Time Coordinated) or Zulu Time. This is the international standard that all world time is set to. This standard was originally governed at the International Meridian Conference in 1884. Every time zone within the world is documented against GMT and is unaffected by daylight savings time. When you hear of GMT being documented in horology, it refers to the ability of the watch to show dual time zones one of which will be in a 24-hour mode. This allows the user to grasp if that time zone is presently in AM or PM.
A watch that has a second hour hand that is set to mark the time at Greenwich. In partnership with a special 24-hour bezel, it allows the user to quickly read the time in different time zones. The additional hour hand can be set to any second time zone the user may want.
See Wheel Train
A precious metal with a specific gravity of 19.5. Gold having various degrees of fineness is used for jewelry and watch cases. In very fine mechanical watches, gold may also be used as the material for the regulating screws on the rim of the balance, for the jewels’ settings, for the wheels, or even for the entire movement.
Known as a precious metal, a soft yellow corrosion-resistant element
If a watch is “gold-filled”, it means that gold was heated and applied to the case of the watch via a soldering process. This technique predates electroplating, and results in a thicker layer of gold than most other plating methods. It is not typically used with watches today.
A coating of gold applied to a non-precious substrate material, e.g. brass.
In a few luxury watches, the craftsman will fit the jewels in a solid gold setting.
See Gold Plating
Gold plating, also known as gilt, is a thin layer of gold that is fused onto another metal to make it appear as if it was gold. The downside is that gold plating tarnishes rather quickly and can leave what looks like a green skin. It’s thickness is measured in microns, but irrespective of how thick the plating is, I strongly advise against purchasing a gold plated watch. It may look gorgeous for a few months but it will tarnish relatively quickly, making it look cheap and tacky.
A way of giving a watch case or bracelet an inexpensive look of gold by electroplating it with a layer of the precious metal. The thickness of such plating is only a few microns and the finish is subject to wear in daily use. This is the main reason many watches are available in two-tone finishes to preserve the gold by restricting it to less vulnerable areas of the watch.
Various colors and references to gold which appears yellow, pink or white
An electronically deposited layer of gold with the thickness measured in microns. “GP, HGE, GE” or any fraction after a number are stamps indicating gold plate.
Harmonic flattened bell in a steel alloy, usually positioned along the circumference of the movement and hit by hammers to indicate the time by sounds. The resulting note and tone is determined by size and thickness. Watches that are provided with minute-repeaters, there are two gongs and the hammers strike one note to indicate hours, both notes together to indicate quarters and the other note for the remaining minutes. In more intricate models, furnished with en-passant sonnerie devices, there can be up to four gongs producing different notes and playing some simple melodies such as the chime of London’s Westminster Clock Tower or ‘Big Ben’ as it is frequently known.
A GPS (Global positioning system) is a satellite based radionavigation system that is owned by the US Government an operated by the US Air Force. A GPS system provides geolocation and time information to a GPS receiver virtually anywhere on earth. Watches with a GPS receiver installed is worn as a single unit that is strapped to the wearers wrist.
A luxury watch with a very high value – normally one that is out of the price range of the person who desires it.
A repeater that creates a sound to mark the hours and quarter hours by pressing a lever.
A mechanical watch that includes a large variety of functions or complications. Watches like this are not meant for practical use, but rather as showcases for craftsmanship.
Can be a highly complex pocket watch or wristwatch equipped with one or more of the following functions: chronograph, perpetual calendar, minute repeater, etc.
A large striking mechanism which, depending on it's a specific version, sounds an audible signal to announce the arrival of full, half, and quarter hours automatically. A second barrel is combined into the movement to power this mechanism. As a set rule, timepieces with Grande sonnerie also have a slide-piece that can be pulled to shut off the audible mechanism. The Grande sonnerie is often put together with a repeater movement.
A watch or another timepiece that chimes at the hour, half hour, and quarter-hours automatically or when the wearer presses a button. The mechanism commonly includes various chimes of various pitches to allow the wearer to know the time within the quarter-hour by hearing alone. Very intricate versions may even include an automaton like a small singing bird.
The gravitational pull of the Earth draws all bodies towards the center of the planet. The acceleration undergone by freely falling bodies is measured in “G”. The influence of gravity on the rate of a mechanical timepiece should not be miscalculated, especially in pocket watches, which are typically worn in a vertical position. The gravitational attraction of the Earth draws all bodies towards the center of the planet. The acceleration undergone by freely falling bodies is measured in “g”. The influence of gravity on the rate of a mechanical timepiece should not be underestimated especially in pocket watches, which are usually worn in a vertical position. Gravity can cause notable disturbances in the rate behavior if the center of gravity of the balance is not placed exactly center on the balance staff. If it is absolutely centered, is there no point along the rim of the balance which is continually drawn towards the center of the Earth with greater force than all other points along the rim, thereby causing either acceleration or deceleration.
Unauthorized sales of new watches at a lesser price that authorized resellers. Typically these are not original and of inferior quality.
The standard for which all 23 time zones are based off of and occasionally referred to as UTC.
After many years of preparation, and immediately after the wholesale cancellation of ten entire days, a calendar reform ordered by Pope Gregory XIII went into effect in Rome on October 15, 1582. This reform eliminated the tiny residual error contained in the Julian calendar, which had been in effect since 45 BC and according to which the year was too long by a fraction of a day: 0.0078 x 24 hours = 673.92 seconds too long, to be exact. The Gregorian calendar compensates for this slight error by dropping three leap years every 400 years. Whenever a secular year (i.e. a year whose last two digits are “zero”) which is not divisible by 400 arrives, that year is not a leap year. Hence, there will be no February 29th in the years 2100, 2200, and 2300 AD.
An engraved ornate pattern, often used on watch dials, comprised of sophisticated intertwined lines.
Surface adornment or texture. An balanced pattern is cut, usually on the dial
To engrave, with the help of a rose engine, a watch’s case or dial with a decorative pattern of slender, sometimes artfully crossing or interlaced lines.
Also known as Engine Turning. This is a very precise engraving approach designed to produce complex, repetitive designs on a material, including those used on dials.
Decoration of dials, rotors or case parts subsisting of patterns made by hand or engine-turned. Dials and rotors decorated this way are generally in gold or silver.
Early in the 1950s, watchmakers at the house of Patek Philippe discovered that the new glucydur balances, which no longer needed inertial weight screws on their rims, could be built in larger diameters without significantly increasing their weight. Larger diameter went hand in hand with an increase in the balance’s moment of inertia, which led to improvements in a watch’s rate performance. Patent protection was awarded to the “Gyromax” balance on December 31, 1951. On this type of balance, eight slit, disk-shaped, regulating elements are borne on axially arranged pins. The elements can be rotated. This outstanding development can be seen as the precursor to the modern annular balance, which has no screws. Although Patek Philippe too initially continued to rely on the familiar mechanism for making fine adjustments in the position of the index as a means of altering the frequency of the balance, the fact remains the precision-enhancing advantages of the “Gyromax” balance can only be exploited to their full potential in combination with a freely oscillating balance spring.
Introduced around 1972, this feature causes the second hand to ‘stop dead’ when the winding crown is pulled out fully to set the time, thus allowing for more easily synchronizing of one or more watches.
A hack feature is one which stops the running seconds hand of a watch so that, when setting it, you will be able to precisely sync your wristwatch to another timekeeping device.
See hacking seconds
Also known as hack seconds or stop seconds. A hacking seconds function permits the wearer to stop the seconds hand, mostly achieved by pulling out the crown to a preset stop, while the rest of the mechanism continues to run and keep the time. It's used to sync the watch with someone else's or with a reference time signal without having to adjust the time.
Also referred to as “stop seconds,” this function will stop the seconds hand when the crown is pulled out. This makes it simpler to synchronize a watch with another timepiece.
Also known as a balance spring, this very thin metallic spring in a watch movement that allows the balance wheel to recoil. It's length can be modified to regulate the watch by making it run faster or slower.
The hairspring is a very thin spring no thicker than a strand of hair in a mechanical watch that causes the recoil of the balance wheel. Can also be known as the balance spring, it's purpose is to regulate the time based on its length and adjustment.
A watch that correctly indicates the various lengths of the months throughout one leap-year cycle. The 29th of February is unknown to them because they lack a wheel which rotates around its own axis once every four years.
Watch with a sprung cover having a circular opening in its center through which the time can be read when the cover is in its closed position. This type of case was most popular on pocket watches. Prior to the introduction of the first shatter-resistant watch crystals in the 1920s, half-hunter cases were sometimes also used on wristwatches. Half-hunter pocket watches usually had a pane of glass in the circular aperture; half-hunter wristwatches usually lacked this pane.
A type of consumer protection going back 700 years. These are marks stamped on a watch case by a company or some official body that carry information. They can guarantee the purity of the metal used in the case. The quality of the watch, the country or city of origin, water resistance, serial numbers, manufacturer, year of manufacture, caliber reference, or trademarks determined by independent inspectors,
A mark which is stamped on the case of a watch to provide various information about the degree of purity of the precious metal used, the country (sometimes city) of origin, the year of manufacture and the identity of the case’s maker. Supplementary hallmarks may show the trademark of the watch company, a reference number and a serial number
Steel or brass element utilized in movements that are provided with a repeater or alarm sonnerie. It strikes a metallic gong or bell.
The hand acts like an indicator that moves over the dial to point at the hour, minute or second. Watches typically have three hands to show the hours, minutes and seconds. Hands can have some very different shapes like a pear, Breguet, sword, skeleton, baton, arrow or more.
A watch that is winded by hand is the same as a manual or mechanical timepiece. It requires the wearer to wind the watch at regular intervals in order for it to keep accurate time. This is achieved by winding the crown, which causes the mainspring to wind up and release energy which powers the watch.
The part of the watch display used to relay information. The watch hands can come in many forms for practical reasons or just for show. In tool watches, it is commonplace for the hands to be shaped differently, as tit can be difficult to mistake for one another.
Refers to a mechanical watch that doesn’t automatically wind. Hand-wound watches are powered by turning the crown by hand to wind up the mainspring.
Also called a manual-wind movement. A mechanical movement that needs periodic winding by hand to function. These regularly include mechanisms to stop overwinding, but nothing to deal with the irritation of forgetting to wind the watch and finding yourself with a dead timepiece.
A timepiece whose mainspring depends upon manual winding..
"In 1900 Hans began his career in Swiss watchmaking when he moved to La Chaux-de-Fonds to work as an English correspondent and clerk with the influential watch firm of Messrs. Cuno Korten, ru Leoppold Robert, where he was paid a salary of 80 Swiss Francs. At the time, Cuno Korten exported approximately one million francs worth of pocket watches on an yearly basis. Cuno Korten laboured with all grades of watches, and manufactured a small portion of watches from the ground up. Hans Wilsdorf was held responsible for manually winding hundreds of pocket watches everyday in his position with Cuno Korten, as well as making sure all watches were kept accurate. Hans Wilsdorf gained immense insight into watchmaking while working with Cuno Korten. He acquired invaluable knowledge about how all types of watches were manufactured around the world."
A metal casing made by creating a bond of titanium and tungsten carbide particles together, in a high-pressure press. The result is an exceptionally hard, scratch-resistant material that can be polished with diamond powder. The resultant ,material is also very brittle and cannot be repaired if damaged.
Haute chronologie is considered very upmarket watchmaking. The term is derived on the fashion industry's haute couture, and creations can occasionally be just as outré.
Direct translation, this French term means “high watchmaking.” It is used to differentiate watches or watchmakers that exude extreme proficiency in watch design, technical innovation and finishing.
Heart-shaped corn, normally used to realign the hands of the chronograph counters.
The calibrations of a production counter help to determine the production capacity for identical pieces in a serially mass produced item. The chronograph is started at the beginning of the process leading to the production of a serially mass-produced piece, then stopped again when the process is finished. The hand on the dial shows how many pieces have been manufactured per hour. This assumes, however, that no more than 60 seconds are required to manufacture each piece.
Also known as a helium release valve. The valve is set in a dive watch to prevent it from being damaged by helium. Dive watches with a water resistance rating of over 300 m (1,000 ft) are regularly worn by mixed-gas divers, who breathe a mixture of helium, hydrogen, and oxygen when working at extreme depths.
Divers sit in a compression chamber, in between dives, filled with the same gas mixture. The helium molecules are so small, they could possibly slip past the watch's gasket and into the case. When the divers leave the chamber and return to the sea level pressure, this trapped gas could critically damage the watch. A result the one-way helium release valve is used to bleed off the helium when the internal case pressure becomes too great.
Before surfacing from great fathomage in a pressurized enclosure, such as diving bell, toxic gases that have been formed in the enclosure are removed and helium is mixed into the air. The helium molecules are lighter than air and can therefore enter the watch. When the pressurized enclosure comes to the surface and is depressurized, the helium rushes out of the watch so fast that the glass on the watch pops out as well. The watch was built to withstand the external pressure from the water depths, not internal pressure. To avoid the glass popping out you can open the Helium Escape Valve on the watch during resurfacing, which permits the helium to escape but prevents water from entering the watch.
Unit for the measurement of frequencies in cycles per second. It's abbreviation is "Hz."
Also known as Hz. See Vibration or vph.
A mechanism in which a disk, printed with a series of digits from 1 to 12, replaces the hour hand. The present hour is visible in digital form, i.e. it is displayed as a digit or digits. One and the same numeral is seen for 60 minutes through an aperture cut into the dial. After the minute hand reaches the “12”, this numbered disk jumps suddenly forward to display the next numeral, thereby indicating that the next hour has begun.
An artificial glass manufactured from a plastic resin. During the 1960’s, a lot of watches used either mineral glass or acrylic crystals. These are not hard to scratch, but very cheaply replaced. In current times, most luxury watches use the highly scratch resistant synthetic sapphire crystals. There are some styles or brands that use the Hesalite (a trade name for a synthetic (acrylic) crystal). The reasoning for this is directly associated to the watch's certification for use in high stress/impact situations. Even though sapphire crystals are less prone to scratching, they can be shattered. They break into tiny fragments that would be hazardous in some environments e.g. NASA specify hesalite crystal for all watches going into space. The Hesalite crystal is shatterproof therefore is maintained on some specific models as a safety feature.
High-tech ceramic is used as a protective shield for spacecraft re-entering the earth's atmosphere. High-tech ceramic is polished with a diamond dust to create a highly shined finish. he ceramic can be injection molded and the pieces can be contoured. It has a very smooth surface and is normally found in black, but can be manufactured in a spectrum of colors.
A watch that purposely copies the design cues of a classic and far more expensive watch without pretending to be that watch, as opposed to a counterfeit or, worse a replica. It permits someone to have a watch that looks and feels of a Rolex or Cartier without going destitute or feeling fraudulent. However, purists still frown on them as the chronographic comparable of a celluloid dickey.
This is a dial with a honeycomb texture. The Rolex honeycomb dial features this design.
Also known as a Swiss lever escapement. The name is derived from the hooked shape of the teeth on the escape wheel.
Horology is the study of time evaluation via sundials, clocks, chronometers, watches, and other timepieces, and their construction.
The art or science of measuring time.
A detail in the construction of some chronographs, an hour counter tallies the number of hours which have elapsed since the beginning of a stop-time sequence. Most hour counters can tally a maximum of twelve hours. When the return-to-zero push-piece is depressed, the hand on the hour counter also returns to its starting position.
Symbols placed around the dial to mark the hours are normally Arabic numerals or Roman numerals.
The hourly time signal will chime every hour on the hour If activated.
A caliber defined by the seconds hand fitted on an axis 90° to the one of the winding stem.
A movement in which the fourth wheel and the crown form a 90° angle with the center of the watch. A small seconds subdial is located at the “6”.
A pocket watch with a cover, which is differentiated by a winding stem at 3 o’clock.
see Hunter Pocket Watch
The hunting case is a case that completely covers the pocket watch.
For eons, hunters and fisherman have used the different phases of the moon to best determine the time to hunt or fish. These watches show the moon age as well as what time the sun will rise and set based on location.
A classically-styled analog watch (normally quartz-powered) that also has digital smart functions like activity tracking and push notifications. (Read our review of one of our favorite hybrid smartwatches here.)
A watch that incorporates mechanical and smartwatch components into the design.
A mechanism that lights up the display on the watch on command. This can include simple electric lights; LEDs; photoluminescent materials like Super-LumiNova, LumiNova, or LumiBrite that absorb and re-emit light; phosphorescent materials embedded with radioactive isotopes like radium; and tritium-filled tubes called trasers among others.
A variety of shock absorber for mechanical watches that's designed to protect a movement's watch balance staff. The incabloc is a shock absorber that preserves the balance staff from breaking if the watch is dropped or impacted.
Developed by Portescap, this adjustment system for mechanical watches does not need the typical index. The outer end of the balance spring is pinched between two elastic rollers. The position of one of these rollers can be shifted with the aid of a star-shaped component, thereby lengthening or shortening of the balance spring and altering the rate of the watch. This job would otherwise be completed by the index system, which is rendered irrelevant by the Incastar solution.
The text of a patent granted to a movement with a jump-type seconds hand describes the independent seconds mechanism as “a mechanism for the step-by-step forward motion of the seconds hand on a gear-driven timepiece movement”. In essence this is nothing other than an typical mechanical caliber. On a watch whose balance has a frequency of 18,000 beats per hour, the independent seconds mechanism counts five vibrations, then releases the seconds hand, which (as ni a quartz watch) leaps forwards by a full second.
A plain mark on a watch dial devised to indicate the hours.
The index hour marker is a line or indicator on the dial of an analog watch that is regularly used instead of numerals
An hour indicator on an analog watch dial, used in lieu of numerals.
A display, e.g. of the time, date, day of the week, month, equation of time, power reserve, time in a second time zone, etc.
The characterizing on the dial of a watch used to represent the hours in place of numerals. In the more luxurious watches, these are usually “applied,” or attached to the dial, rather than printed on.
On watch movements with indirect central seconds, the impulse for the seconds hand comes from outside the flow of energy passing through the gear train. For this reason, this type of seconds mechanism is frequently found on calibers which were originally constructed to support small seconds subdials and subsequently rebuilt to support a “sweep” seconds hand. Contemporary calibers are usually manufactured to support a centrally axial “sweep” seconds hand. Normally for this reason, they most often have direct central seconds, i.e. the impulse for the seconds hand is within the flow of energy passing through the gear train.
A lot inexpensive quartz clocks and watches utilize a technique known as inhibition compensation. The crystal is deliberately made to run somewhat faster. After manufacturing process is completed, each module is calibrated against a precision clock at the factory and adjusted to keep accurate time by programming the digital logic to skip a limited number of crystal cycles at constant intervals, such as 10 seconds or 1 minute. For a typical quartz movement this allows programmed adjustments in 7.91 seconds per 30 days increments for 10-second intervals (on a 10-second measurement gate) or programmed adjustments in 1.32 seconds per 30 days increments for 60-second intervals (on a 60-second measurement gate). The distinct advantage of this method is that the use of digital programming to store the number of pulses to suppress in a non-volatile memory register on the chip. It is less expensive than the more historic technique of trimming the quartz tuning-fork frequency. The inhibition compensation logic of a few quartz movements can be controlled by the service centers with assistance of a precision timer and adjustment terminal. Many cheaper quartz watch movements do not allow for this functionality.
An in-house movement is classified as a watch movement that a brand manufactures by themselves. A generalization of what “by themselves” means is a fluid definition as mechanical watch movements are made up of a lot of small parts. Often times some or a lot of those pieces are produced by outside suppliers
An additional protective cover (dome or cuvette) beneath the outer back cover of a watch. This type of additional cover is most commonly found on pocket watches. Early wristwatches with hinged cases were occasionally also equipped with inner covers
A watch strap or bracelet that integrates into the case and is not detachable. It's most frequently found on fashion watches with a plastic or silicone rubber case and strap.
Ionic plating is a procedure that allows a darker grey to black compound to be applied to stainless steel watch cases and bracelets giving the watch a modern look over the standard appearance of metal.
Isochronism refers to a mechanical watch that will work at the same rate irrespective of whether it is fully wound or not.
International Watch & Jewelry Guild Show has about 8,000 members from over 70 countries, is the world's most active central exchange for buying and selling watches, time pieces, jewelry, and diamonds. It was founded in 1988 by Burley Bullock, creator of what they call the most successful watch buying program in the U.S. Watcg shows are coordinated by Olga Cortez Bullock and Christina LeDoux. IWJG members are invited to about 10 to 12 trade shows per year. The watch shows are usually held in luxury hotels. IWJG membership is required in order to attend our trade shows. The public may not attend. Members also receive eight informative newsletters per year containing up-to-date price guides on the best-selling watches.
Sorry, this hasn't anything to do with jewels in the ornamental sense. They are sapphires or rubies (usually synthetic), that are shaped into gear bearings to reduce friction and increase the life of the movement between servicing.
This is a machine element for reducing friction and uses jewels such as synthetic rubies and sapphires. The jewels are set in the
A cylindrically shaped synthetic gemstone (usually a ruby), with a hole drilled into its center. Jewels are pressed into plates, bridges, and cocks to reduce friction and minimize wear in the pivot holes drilled into planar components. The rapidly rotating pivots of a gear train spin inside the jewels. In very fine watches, the walls of the holes in the jewels are not cylindrical in shape, but are rounded into an olive-like shape, whence the technical term “olive” or “olive-cut jewel hole”. The rounding on the walls of the hole further reduces friction in the bearing because it minimizes the area of contact between the jewel and the pivot. Furthermore, an olive-cut jewel hole gives greater freedom of movement to the pivot.
Pallets containing with ruby pallet jewels.
Sapphire or Rubies that diminish friction by acting as bearings for gears in a mechanical watch.
Synthetic rubies or sapphire or even real rubies are used as bearings at the heaviest points of wear in a watch movement in order to lessen the friction in-between moving parts and increase a movement’s lifespan. Jewels have a naturally slippery surface as opposed to metal. The coefficient of friction in-between two pieces of steel is about 0.58, while the coefficient of sapphire on steel is about 0.15. Jewels are only used to boost the accuracy of the movement and are not for decoration.
The familiar cycle of three ordinary 365-day years followed by one 366-day leap year was initiated by Roman emperor Gaius Julius Caesar. The year was defined by the Julian calendar, however, is 0.0078 days longer than the actual astronomical year. Pope Gregory XIII corrected the error, which in the course of many centuries had accumulated to ten full days, by instituting the Gregorian calendar in the year 1582.
See Jumping Hour
A jump hour indicator replaces that of the hour hand. Instead of the hour hand continuing to move in the circular motion, it is displayed by means of numerals in a window on the face of the watch.
In place of using analog hands and marks on a dial, jump hours or minutes are a way of creating a digital display using a mechanical movement. In a jumping display, numbered discs revolve behind the watch face and are made visible through an aperture. It's called a jumping display because, where hands move gradually from one mark to the next, the numbers in the aperture remain static until the next minute or hour arrives, then jump ahead.
Also known as deadbeat seconds, this is a way to allow mechanical watch movements shift the seconds hand in discrete one-second interval in a single tick like a quartz movement. Pendulum clocks have used deadbeat seconds since 1675, but modern mechanical movements usually tick five to ten times per second. Some haute chronologie watches can be made to display deadbeat, though the reason for doing this is simply to show off the complex mechanism needed to achieve it.
Feature showcasing the digital display of time in a window. The indication changes almost instantaneously at every hour.
The current standard for displaying the purity of precious metals indicated by the abbreviation "k." 24k gold is pure and 18k gold is 75 percent pure. The adding of other metals into the gold is required because pure gold is too soft to be practical.
As with all jewelry, a karat is an indicator that shows the purity of a metal such as gold. Pure metals such as gold are too pliable to use in watches, they’re made into an alloy to increase its strength. The ratings show the proportion of pure metal to other metals by using the karat scale of 1/24, 24k gold is pure, whereas 18k gold is 18 parts of pure metal to 6 parts of other metal.
A device similar to a tourbillon. The karussel was invented in 1892 by a Danish watchmaker named Bonniksen as an alternative to the tourbillon, which is more difficult to make and significantly more costly. A tourbillon usually turns around its own axis once each minute. The oscillation and escapement system inside the karussel describes a circular arc of 360° once every hour. Some karussels have a shorter orbital cycle. In addition to its slower speed of rotation, another essential difference between a karussel and a tourbillon lies in the propulsion of the rotating organ. A tourbillon is made to rotate by the fourth wheel, which means that the rotations of the tourbillon cage are indispensable for the to and fro oscillation of the balance and thus for the function of the entire movement. If the tourbillon comes to a standstill, so too does the entire watch movement. A karussel is usually propelled by the third wheel. The watch therefore continues to run even if the karussel, which is usually crafted as a plate, should come to a standstill. Karussels were first built into wristwatches in 2001.
Loops on a watch strap or band designed to keep the surplus end length of the strap in place after its been fastened.
A key set is a term used for a watch that is set using a small key, rather than winding the crown. While not as common anymore, most antique pocket watches are were you would find a key set movement.
A watch whose mainspring is manually wound via the crown.
The keyless works permits the movement to be wound and the time set by the winding stem. It permits for two (or more depending on the movement) winding stem positions that engage the different gears trains in the movement.
A technology creates and manufactured by Seiko for its superquartz movements. Its function is to change the wearer's movements into electricity to keep the watch battery fully charged.
Is a manufacturing process that is usually performed on a lathe, where a pattern that can be a mix of straight, angled or crossed lines are rolled into the material.
Kew Observatory in England was originally created in the 1850's for King George III to test timepieces. A Kew A Certificate meant that the certificate ws awarded for having some of the best timing results of the time.
A vegetable product, the resin of certain trees found in the Far East (China, Japan), which gives a fine black or red color. The term may also be used to denote articles made of several layers of hardened lacquer.
This is a watch made by Rolex which features the President style bracelet and is formally known as a Rolex Datejust.
A majority of quartz watches have a built in lap memory which can cache the history of lap times in a race for viewing later.
A chronograph or stopwatch function that can record the time for a personal event in a race, including a runner's laps. When each lap is counted, it automatically returns to zero to time the next lap.
The surfaces or edges of watch components can be smoothed and polished with the aid of a lapping (or polishing) machine. This polishing enhances the visual appearance and the value of a movement
Laser Engraving uses a laser beam to change the surface of an object. This process is commonly used to create images on the material that may be seen at eye level. To do so, the laser creates high heat that will vaporize the matter, thus exposing cavities that will form the final image. It uses the laser for marking the surface of an item
Liquid crystal display or LCD watches are another phrase for digital watches and use a numeric Arabic display by using a liquid that’s enclosed between two clear plates. This is activated by electronic impulses, the numbers are made up of seven lines that all form the number eight when fully lit.
According to the Julian calendar, every fourth year has an extra day added to it at midnight, February 28. Because of this additional day (February 29), a leap year has 366 days, rather than the 365 days which comprise an ordinary year.
Leap or bissextile years each have 366 days and happen every 4 years (with some exceptions, Calendar, Gregorian). Some watches are able to display this datum.
Abbreviation for “light emitting diode”. These opto-electrical elements were used in the 1970s to indicate the time on quartz watches. Because the display saps so much energy when lit, it was kept dark unless specially triggered by pushing a button. This shortcoming soon led to its obsolescence, and the LED was replaced by the LCD.
In this form of construction for watch movements, which is named after French watchmaker Jean-Antoine Lépine, the wheels and the balance share a common plane and run on one side of the plate beneath the bridges and cocks. Furthermore, in a Lépine caliber, the winding cum setting crown, the center of the dial, and the axis of the seconds hand are all aligned along the same line.
A lepine watch is a pocket watch without a cover, characterized by a winding stem at 12 o’clock.
See Lepine watch
Also known as an anchor escapement. An escapement that utilizes an anchor-shaped lever together with two pallets to lock and unlock the escapement wheel's teeth. A lever escapement is piece of the movement that divides into two pallets that lock and unlock the escape wheel teeth. This process is controlled by the balance wheel which engages the opposite end of the lever making the escape teeth move on the pallets and life the lever so it can impulse the balance.
Most frequently found on the railroad, a lever set watch requires the user to remove the crystal and pull a small lever in order to set the time.
In the 1990's, LIGA was a innovative MEMS fabrication technology, resulting in the design of components showcasing the technique's rare adaptability. Several companies that begin using the LIGA process later changed their business model (e.g., Steag microparts becoming Boehringer Ingelheim microparts, Mezzo Technologies). Currently, only two companies, HTmicro and microworks, continue their work in LIGA, benefiting from limitations of other competing fabrication technologies. Due to its lower production cost, UV Liga is engaged more broadly by several companies, such as Tecan, Temicon, and Mimotec in Switzerland, who dispense metal parts made of Nickel and Nickel-Phosphorus in the Swiss watch market.
A feature that utilizes diodes that emit light when energized. These were utilized in the first digital watches but drained so much power that they could only be illuminated for a fraction of a second by pressing a button, with the display being invisible until the button is pushed again.
A old French unit of measurement used in watchmaking, equal to 2.2558291 mm.
A traditional unit used to measure the dimensions of watch movements. The ligne derives from the old French foot or “pied due roi”. An accepted diameter for circular movements is 11 lignes. Rectangular movements sometimes measure 8¾ x 12 lignes. One ligne is equivalent to 2.2558 millimeters. One French foot measures 12 inches or 144 lignes. A foot is abbreviated with a single apostrophe ('); an inch is abbreviated with twin apostrophes (''); a ligne is abbreviated with three apostrophes (''').
A watch that is assembled and sold in a limited number of units that are often numbered. The purpose of doing this is to increase their value of the time piece.
See Limited Edition
Also known as Ligne, ancient French measuring unit maintained in horology to show the diameter of a movement. A line equals 2.255mm and are not divided into decimals. Therefore, to indicate measurements inferior to the unit, fractions are used.
Linen dials are one of dial type for Rolex time pieces. A linen dial is a type of textured dial which has dozens of small vertical and horizontal 'hatch marks' that look similar to linen like material. Fairer colors like white and cream are more frequent, with darker colors like gray and black being much more rare. I've looked and looked and have been unable to find out exactly how the linen like texture is created so if you know, then leave a comment down below.
A flat display on a digital watch that utilizes liquid crystals that are sealed in a layer between two transparent plates in a series of sections. When an electric current is applied to one of the sections, its optical attributes change and it becomes opaque. This allows it to display digits, letters, and symbols depending on the display's design.
Liquid Crystal Display that displays time electronically by means of a liquid incapsulated in a thin layer between two transparent plates.
Is a nickname for second hand where the luminous dot is at the very tip. This is commonly found on the Tudor Submariner.
Lubrication is used to reduce friction caused by the running of wheels and other parts. There are definite high friction points that need to be lubricated with specific low-density oils such as the pivots turning inside jewels, the sliding areas in-between levers, and the spring inside the barrel which needs a special grease, as well as numerous other parts of a movement.
Curved protrusions from a wristwatch case for the attachment of a strap or bracelet by means of spring-loaded pins
The distended pieces of metal at the top and bottom of a watch case where the strap is attached. The two opposite ends of the lug hold a spring bar, which holds the strap in place.
Often referred to as horns, lugs are protrusions on the watch case. There is a spring bar between the lugs that are used to fix the strap or bracelet to the case.
The 'lug width' is the internal width measured between the lugs (where the watch strap fits) of the watch
Conversationally referred to as “lume,” luminescence is identified by the glow given off by watch numerals, indices and hands that have been painted with a photoluminescent material (“lumed”). Earlier manufactured watches used radioactive radium to create lume, now most modern watches use non-radioactive phosphorescent substances like strontium aluminate.
Luminescence refers to emitting rays of light. A luminescent material is deposited on numbers and hands in order to read the time in the dark.
Watch (dial, hands) that glows in the dark. Photoluminescent paints that absorb energy from external light sources in the UV spectrum and exude it over a period of time. Today there are 3 main materials for creating Luminescence: LumiNova (zinc sulfide-based), Super-LumiNova (up to 10 times brighter than LumiNova) and Tritium gas tubes (GTLS). It's worth noting that GTLS is not allowed in select countries.
Luminous markers and hands are created by putting a glow in the dark coating to the respective indicator permitting them to illuminate automatically in a darker environment.
Dial from which the time can be read during the night and without additional illumination. To accomplish this, the numerals or indices and the hands are filled with a luminous material. Just seven years after Marie and Pierre Curie’s 1898 discovery of radium, the Büchler & Co. quinine factory in Braunschweig, Germany, began to market luminous dials and hands for watches. Pure radium is highly radioactive, so this element is no longer used on luminous dials. Tritium, a radioactive isotope of hydrogen with an atomic weight of 3, has likewise become obsolete. Watches with tritium as their luminous material can be recognized by the words “Swiss Made — T” on the dial. In place of these radioactive substances, modern glow-in-the-dark dials rely on alternative substances which are non-radioactive yet nonetheless luminous, e.g. Super-LumiNova.
Phosphorescent paint is normally used as body paint, but can be used on watch and clock dials, on children's walls and outdoors. Safety concerns and tighter regulations in consumer products such as clocks and watches, have seen an increased use of phosphorescent rather than radioluminescent substances. Radioluminescent paint sometimes is still be preferred in specialist applications, such as diving watches.
During one lunation, which is equivalent to approximately 29.5 days, the moon progresses through one full cycle of its phases: i.e. from new moon, through first quarter, full moon, and last quarter, to the next new moon.
Metal components within a watch can regularly be magnetized when introduced to magnetic fields, therefore causing a serious loss of accuracy. This happens normally when the balance spring becomes magnetized and sticks to itself, thus causing the watch to run faster than normal. Fortunately, this problem can be fixed quickly and easily at a watchmaker (or at home, even). It is enough of a problem, however, that some high-end watchmakers use soft-iron cages to protect the movement from magnetic fields, or use silicon balance wheels that do not become magnetized. (Learn more about anti-magnetic watches here.)
See Cyclops
Maillechort is French for Nickel silver, German Silver, new silver or alpacca. Maillechort is a metal alloy consisting of nickel (12 to 25%), copper (47 to 65%) and zinc (10 to 40%), which has good corrosion resistance and is also utilized for watch cases. It provides better robustness than brass. Nickel lends the component nickel silver the feature of little oxidation. Therefore galvanic postprocessing of the material is unneeded — it can be left in its "natural" state,
The main plate is the base on which all the components of a mechanical watch movement are mounted.
A main spring is torsion spring that becomes tightened when a watch is wound, thus storing the energy of a watch. The power of the spring unwinding is what powers the watch. The mainspring is enclosed in a small drum called a “barrel.”
The main base plate that acts as the foundation for a watch movement.
The main spring on a watch that provides it with the power to operate. It's usually created from a flat, spiral torsion spring of spring-steel ribbon set in a barrel attached to a toothed disk. As it uncoils, it turns slowly on its arbor and keeps the gear train in motion.
The trademark of Vacheron Constantin is shaped like a Maltese cross. A similarly shaped component is used to limit the extent to which the barrel can be wound. Together with a finger mounted on the barrel arbor, the Maltese cross compensates for the greatest differences in torque in the powering of mechanical watches and clocks with gear trains. This elaborate technique is only rarely used nowadays and is found only in especially fine watches.
A mechanical movement that's manually wound using the winding crown. The motion made by the user’s fingers to the crown is forwarded to the movement via the winding stem, from this to the barrel through a series of gears and finally to the mainspring.
See Manual Wind
Place the crown (winder) between your thumb and forefinger and turn the crown forward (clockwise) with a long stroke. The crown will rotate in both directions, but can only wind in the clockwise direction. To fully wind a watch requires 15 to 25 full 360-degree turns (this will vary depending on the watch). Turn the crown clockwise until it stops abruptly and cannot be wound any further. A manual timepiece should not be wound until resistance is felt and the crown will no longer turn clockwise, whereas an automatic watch can be found forever without risk of damage. Your fully wound watch will run for at least 24 hours.
The manual wind movement is another phrase for mechanical movement meaning that the wearer must manually wind the crown for the watch to work. Usually, once the watch is fully wound it will keep time for approximately 35-45 hours before needing to be rewound again.
Created in 1842 by Jean-Adrien Philippe, crown winding allows one to use the crown of the watch to turn the barrel and wind the mainspring. This method is often referred to as self-winding, keyless winding, or hand winding. Charles Antoine Jaeger-LeCoultre is also named as the originator of the crown winding. In 1847 he created a crown winding with a rocker, this allowed winding and adjusting the hands using a single crown. Today, the LeCoultre method is typically used for all watches. The switching mechanism works by pulling out the crown to the required position where the desired functions can be performed. Watches can include one or more crown positions for various functions, including winding, setting the main time or second-time-zone, and setting the day and date.
See Manual Wind Movement
According to the unwritten laws of watchmaking, a company that makes watches can only describe itself as a “manufactory” if it makes at least one ébauche (movement blank). The companies whose artisans assemble readymade ébauches to produce finished watches are known within the industry as “établisseures”. The small and elite circle of mechanical-watch manufactories currently includes, among other names, Audemars Piguet, Chopard, Roger Dubuis, Girard-Perregaux, Glashütte Original, IWC, Jaeger-LeCoultre, A. Lange & Söhne, Patek Philippe, Piaget, Rolex, and Zenith.
A watch company that utilizes at least one of its own movements that have been manufactured in house.
A French term, that is normally shortened to “manufacture,” that refers to a watch company that manufactures its own parts (including its movements) in its own facility (“in-house”), rather than assembling watches from parts made by third-party suppliers.
In watchmaker´s parlance, the French word for “marriage” describes the compilation of many, usually authentic components taken from various and sundry watches to assemble one complete new watch. Well-made mariages are difficult to identify, but even successful ones significantly reduce the value of a timepiece.
An accurate timepiece normally found on a ship that is utilized for determining the longitude. The timepiece is found in a box and is mounted in a horizontal position to maintain precision.
Collector’s term to differentiate the changes in dials as time passes. Generally limited to professional models. Changes include font differences, font sizes, gilt/non gilt, etc.
Elements that are printed or applied on the dial and is used as reference points for the hands to indicate hours, fifteen or five-minute intervals.
A modern term that has come to mean a dial that has oversized hour dots, primarily used to describe submariners and GMT models.
See GMT
Generally, this is a graduated scale located on the bezel or dial that permits the wearer to convert one type of measurement into another.
A mechanical movement attains it's power by a main-spring and works with the balance wheel.
A clock or watch powered by a mainspring or descending weight. The regulation of the rate of these timepieces is accomplished by a balance with a balance spring or by a swinging pendulum. The development of the mechanical gear train clock probably resulted from the mechanism used to propel planetaria, i.e. devices which depict the motion of the planets. The first such artifacts date from the late 13th century. The oldest mechanical gear train clock in German-speaking Europe is probably the clock in Strasbourg cathedral. This clock was completed in 1352. Functional gear train clocks first appeared in England towards the end of the 13th century.
A watch movement gets its power via a mainspring through a gear train and an escapement. There is no electrical power supply.
Mechanical watches are the most time honored watch. They usually contain approximately 120-180 individual parts. This type of watch runs without any electrical source and can consist of manual wind or automatic watches.
The name ‘Mercedes’ hands derive from the three-pointed star in the hour hand, that closely resembles the Mercedes Benz logo. Rolex never said why they created these hands, and if there’s a relation to the car brand or other reasons for their choice. However it’s save to assume that the “Mercedes” star in the large open circle of the hour hand, makes a more stable area in which luminescent paint can be applied. Visually it also helps to distinguish the hour hand from the other hands in low-light settings.
The most typical unit of measurement when referring to the water resistance of a watch. Relates to how deep a watch is able to go, testing is done in a controlled laboratory.
Watches for diving made by Rolex that show depth in meters and then in feet are referred to as Meters First watches.
The perfect blend of sport and fashion. A stylish watch that can be used as a perfect accessory on any occasion, typically used by active and fashion oriented people. The metropolitan watch case is made from 40mm high grade corrosion-resistant stainless steel (316L) reducing the risk of allergy.
A micrometer screw is positioned on the regulator, allowing to be able to shift by a minimal and perfectly gauged range so as to obtain accurate regulations of the movement.
The micro metric regulator is a timekeeping regulator used in high grade watches that can be finely tuned by the adjustment of a small screw.
A micron is a measurement of the thickness of gold plating. One micron is a thousandth of a millimeter.
A rotor located inside an automatic watch that is very small and thin enough to be set inside the movement instead of rising on top.
A rotor, integrated into the plane of the movement, which automatically winds the mainspring of a self-winding watch. The motivation which led to the invention of calibers with micro-rotors was the desire to build very slim and thus very elegant self-winding wristwatches. Constructions that rely on old-fashioned hammer-type oscillating weights (which move only through an arc rather than completing a full circle) or which rely on central rotors, Universal Genève followed suit in 1958 with the slim “Polerouter”. Piaget presented the Caliber 12 Pl in 1959: just 2.3 mm slim, it was the world’s slimmest automatic watch. Patek Philippe’s classic Caliber 240, which is 2.4 mm slim, has a micro-rotor made of 22-karat gold. Chopard’s LUC 1.96 debuted in 1996: this manufactory caliber has twin barrels, is 3.3 mm slim (including its jump-type date display), and has a power reserve of approximately 70 hours. are both situated in a plane above the plane of the movement and are consequently thicker than micro-rotor calibers. Micro-rotor calibers have not won a very large share of the market, but have nonetheless become a fixed feature in watch technology. The pioneer of the micro-rotor was Büren Watch Co., which received a corresponding patent in 1954. Three years later, this company debuted its “Super Slender”, which was a mere 4.2 mm thick.
This is a watch which measures around 34 to 36mm, smaller than a regular men's watch.
Similar to a watch link, a Milanese style bracelet is manufactured out of metal. To create this look, small metal pieces are looped together to create a mesh. This mesh was at first designed to have the look and feel of leather while being breathable. This style originates in Milan, which is where the name Milanese comes from.
This is based on 24 hours as opposed to 12 hours and does not make use of am or pm. This allows for more accuracy with less chance for confusion as to any specific time.
See 24-hour time.
Military time is commonly referred to as the 24-hour clock. To convert 12-hour time to 24-hour time, just add 12 to any p.m. time. To go from 24-hour time to 12-hour time, simply subtract 12 from 13 to 24.
See Field watch.
Milling is done on non-ferrous material in sheets and plates. Once the chipping process is complete, the workpiece is polished. Sometimes deburring is necessary and if required, Bulgari uses two different procedures. This chiefly depends on whether the watch components are to have either a shiny or satin finish. Only once the polisher has the part in his hand, can they see just how good the turning or milling process is. "It only happens on rare occasions, but if there are machining faults, we only see it after the polishing step. But then a major part of the value-added process is already been completed.
Heat-hardened glass is approximately ten times harder than plastic. Exceptionally scratch resistant but has to be replaced if they do get a scratch.
Essentially a form of synthetic glass, mineral crystal is more scratch resistant than plastic but when it gets a scratch is in essence impossible to polish.
The most frequent type of material used in watch crystals. It's made of natural or synthetic glass that has been chemically or heat tempered to a hardness level of 5 to make it more scratch-resistant.
A minute repeater is complication that strikes an audible sound on hours, quarters and minutes using a gong. A notably complicated accomplishment, minute repeaters can increase the value of a watch exponentially and use a slide or button on the case to activate.
A repeater watch that chimes the quarter hours and minutes after the hour, but not the hour itself.
A self-governing mechanism that is separate to the basic calibre and is supplemental to the movement to have an additional function available like a chronograph, power reserve, GMT, perpetual or full calendar.
Invented by Austrian mineralogist, Friedrich Moh, the scale is a unique manner of measuring a mineral’s hardness and scratch resistance. The scale ranges from talc, the softest, to diamonds, the hardest for example, talc= 1, gypsum= 2, calcite= 3, fluorite= 4, apatite= 5, feldspar= 6, quartz= 7, topaz= 8, corundum= 9, diamonds= 10. The vast bulk of gemstones has a rating of 6 to 8. It should also be notable that sapphires have a rating of 9, and mineral crystals have a rating of 6.
A chronograph watch that uses a single button to work. The vast majority of stopwatches need two buttons, one to start and stop and another one to reset. A Mono Pusher complication is enabled to do all three operations on the same button.
A mono-pusher is a type of chronograph that is operated using a single button rather than two or more.
This is a single button stopwatch, which uses the same button for start, stop and reset.
A stopwatch that is able to be started, stopped and reset with a single button rather than two.
Displays phases of the moon, along with moon up and moon down time. Moon up happens when it reaches the highest point in the sky relative to your current location; moon down is the lowest, typically on the other side of the Earth
One of my specially favorite complications, the moon phase is a window that showcases the various phases of the moon
A complication that shows the age or phase of the moon as it waxes and wanes, usually with two miniature moon discs revolving beneath the display, which becomes visible through an aperture.
A complication that shows waxing and waning of the moon as it circles the earth. This complication is shown in a window on the watch dial.
Has an appearance of a cross hatch pattern which is found on president bracelets.
Mother of pearl is the creamy white, blue or pink gleaming interior of a freshwater mollusk that is commonly used for dial decoration.
Also called the dial train. The gear train that interlinks the central wheel arbor to the hour hand and is engaged when the crown is pulled out to set the hour and minute hands to the exact time.
The motion works carrying the hours and minutes hands. They make up the gear train that shortens 1 hour, minutes hand, to 12 hours, hours hand and also allows the hands to be set with the keyless works.
A movement is the inner mechanism of a watch that not only keeps time and but powers the watch’s functions as well.
Also known as a caliber. The inner mechanism of a watch that permits it to operate, to mark time and to perform its various functions. The three most critical movements are mechanical, automatic, and quartz. A watch company can make its own movements or source them from a third party to put in its watches.
The inner-working mechanism of a watch that can be either automatic, mechanical, hand-wound, or battery powered. A majority watch manufacturers refer to their movements as “calibers.” A mechanical movements main components are a mainspring, gear train, an escapement and a balance wheel. A quartz movement is comprised of a battery, a microchip circuit, a quartz crystal and a stepper motor. Many luxury movements, both quartz and mechanical. are manufactured in Switzerland by either watch brands themselves or from large movement manufacturers like ETA and Valjoux. Japan and even China have their own successful watchmaking industries.
See ébauche.
A multifunction watch can also be called a master calendar. While chronographs count the finer details of the passage of time, including seconds, minutes, and hours. A multifunction watch is specific in its ability to track a day of the month or week as well as the time of day.
Multi-Functional watches are like the Swiss Army knives of watches, they do much more than just tell time. Some functions many include altimeters, chronographs, alarms, calculators, compasses, barometers, tide tracking, temperatures and so many more.
A watch with a complication which allows it to play an short piece of music.
French term for a watch which is as transparent as possible and in which neither the movement nor the means of propulsion are visible
A patented creation of watchmaker Vincent Calabrese and produced by a Swiss manufacturer by the name of Jean Marcel. The Mystery automatic mechanical watch does not use hands to indicate hours, minutes or seconds. In place of the traditional hands, a jumping hour window moves clockwise around a minute scale while a second indicator, an arrow, also ticks around. Breathing gently on the crystal causes the word "mystery" to appear.
Its headquarters is located in Switerland. The company oversees numerous companies marketing, including the marketing for BaselWorld.
A NATO band is made from a nylon fabric strap with an additional keeper strap added to run behind the watch and prevent it from slipping off if one of the lug springs should give way. It's designed to be adjustable to a number of sizes including the additional space to fit over clothing. It was primarily developed by the British Ministry of Defense in 1973 and gets its name from a shortening of the term "NATO Stocking Number."
A NATO Strap is a band designed in a military style and is made from waterproof canvas or nylon. These are often available in a variety of colors.
A lot people are developing an allergic to nickel which was at one stage being used underneath gold-plating to smooth out imperfections in the base metal. Since nickel was found to be an allergenic substance, the amount of nickel that was being used has been gradually reduced. Nickel has been replaced by using one or two layers of copper underneath the gold or rhodium plate to do the job that nickel used to. All Rotary watches are well within EEC guidelines but there is no watch that can be called 100% nickel free.
Nickel is a base metal that was once regularly used to make watch cases and was usually plated with either gold, silver, or chromium.as a result of many people showing an allergic reaction to nickel, it has had to be phased out. When nickel is used, it's process includes it being encased in one or two layers of copper, then plated with gold or rhodium.
The hour markers on a nipple dial are round shaped and produce slightly.
Trade name of a nickel-iron alloy, resisting magnetization that is utilized for modern self-compensating balance springs. The level of this material is indicated by the numeral following the name in decreasing value from 1 to 5. As a trading name, Nivarox is a German acronym for “Nicht variable oxydfest” or “Non-Variable Non-Oxidizing” translated to English. The Nivarox alloy is used predominantly in the watch industry but is used in certain medical equipment and surgical instruments.
A watch is nonmagnetic when it is protected against the deleterious effects of magnetic fields. To accomplish this, components which are most susceptible to disturbance by magnetism are crafted from materials which cannot readily become magnetized, for example, balance springs made of elinvar or nivarox are well balanced and crafted from brass, nickel, or beryllium bronze. Furthermore, different nonmagnetic metals are used for components such as the pallets, escape wheel, and roller or roller table. Another option is to encase the entire movement inside an additional inner case crafted from a highly conductive alloy. This inner case restricts magnetic fields from building up inside it.
In watch making a manufacturer will use either Arabic or Roman numerals
A watch that is tough, effortless to clean and to keep sterile and has a pulsimeter to permit a nurse to quickly measure a patient's pulse. It differs slightly from a doctor's watch in that it is built upside down so it can be attached to a blouse and still be legible.
A watch that has been observatory-tested for precision that obtained the relevant rating chronometer certificate.
An oil sink is essentially a recessed pool that surrounds a pivot and holds a small amount of oil to lubricate the gears.
The original geared clocks were equipped with only one hand, which was the hour hand. Abraham-Louis Breguet’s famous “Souscription” pocket-watch was a one-handed watch. The time can only be approximated by consulting the dial of a one-handed watch. Wristwatches of this kind are rare, but not wholly nonexistent.
Minute graduations on an open minute dial are disconnected.
O-Ring, also known as a gasket, ensures a water-resistant seal between two moving parts, for example: the case back, and the case; and the winding crown and the crown tube. Gaskets can be O rings, flat, or shaped, and can be made out of rubber or plastic.
In a self-winding movement, the oscillating weight is a body that is free to rotate and connected with the barrel via a gear train. When the movement is in a non-horizontal position, gravity causes this weighty mass to fall towards the center of the Earth. The kinetic energy generated during this fall is transferred by a gear train to the barrel, where the mainspring stores it as potential energy.
The regular movement of a body, such as balance wheel or pendulum, between two points from one extreme to the other and back again. Anything with a regular oscillation can be used to keep time.
The Rolex Bubbleback was also known as the Ovetto, which means little egg, due to the shape of the case.
An oyster is the large center link bracelet found on sport model watches.
Named after the Rolex Oyster, this is a flexible three-link metal bracelet with a deployment clasp.
Observatory trials was a system used to measure time in a precise method. Originally, there were two major brands that participated in the Observatory Trials, which were the brands Omega dn Patek Philippe.
Pad Printing is a printing process whereby you can transfer a 2-D image onto a 3-D object. This is accomplished by using an indirect offset gravure printing process that has an image that's transferred from the cliché with the use of a silicone pad onto a substrate. Pad printing is utilized for printing on items that are normally difficult to print on. Such items include medical, automotive, electronic objects, as well as appliances, sports equipment and toys.
A pair case watch is a pocket watch that is sheathed in a second protective case in addition to its own.
The escapement transmitting piece of the motive force to the balance. This is to maintain the number of oscillations that are unchanged by freeing a tooth of the escape wheel at one time.
The pallet fork is one piece of the escapement. The pallets on the pallet fork connect with the escape wheel and lead to the pallet fork to moving back and forth. This motion gives energy to the balance wheel, causing it to oscillate.
One of the most complex components in mechanical watches, the pallets are shaped like a ship’s anchor, whence their French name “ancre”. Usually made either of brass or steel, pallets consist of several components, including the lever, the pallet staff, the pallet stones, and the dart or guard pin. The purpose of the pallets is twofold: to convey energy from the gear train to the balance, thereby keeping the latter in oscillation; and to prevent the gear train from racing ahead and quickly exhausting the energy available to it from the barrel.
This is a collectors term that refers to the color of a dial. Usually reserved for Rolex Daytona, the bulk of the dial is white while the sub dials are all black.
Abraham-Louis Breguet used this word to characterize a shock absorption system which he invented. In order to protect the delicate pivots of the balance staff, Breguet affixed the corresponding jewels in elastic steel arms.
Patent Pending
This means that a patent has been issued.
As watches age, some of the parts may change color. This is known as patina and is not considered damage on a watch. Usually the hands and dials develop a patina over time.
Is a number of jewels or stones set close together, typically found in the dial or case.
A pedometer is a complication that calculates the amount of steps taken by the wearer.
The pendant is essentially the neck of the pocket watch where the crown and bow is located.
Nickname for the blue and red bezel inserts for Rolex GMT and GMT II models.
A type of decoration applied to watch movements. It consists of small, overlapping circles. The word is French and means quite literally “pearling.”
Perlage is a cloud-like decoration on the plates and bridges of the watch.
A braided synthetic polymide material watch strap which is made from fibers similar to nylon
A calendar complication that can automatically take into consideration the number of days in the month, leap years and other factors depending on its complexity.
A calendar complication that changes the watch’s calendar for the varying length of months as well as leap years.
A perpetual calendar complication is a very state-of-the-art version of the typical date window display on the common wristwatch. These watches can even account for leap years.
There are many ways that I can personalize your watch. Personalization options normally includes options like lines of some text, initials, or a special personal symbol that can incorporated somewhere into the watch design.
A complication that chimes to mark the hours as they go by.
PVD is a coating of titanium nitrate that is applied to the watch and then covered by a coating of gold to obtain a gold color finish to the watch.
Physical vapor deposition (PVD) characterizes an array of vacuum deposition methods that can be used to produce thin films and coatings. PVD is identified by a process in which the material changes from a condensed phase to a vapor phase and then return to a thin film condensed phase. The most regular PVD processes are sputtering and evaporation. During the PVD processed source material is unavoidably also deposited on most other surfaces interior to the vacuum chamber, including the fixturing used to hold the parts.
A dial which has a centered which is raised and flattened with hour/minute markers below the raised center.
A metal platform that has several tiers for the gear train. The base plate of a movement normally integrates the dial and carries the bearings for the primary pinions of the “first floor” of a gear train.
A larger than normal watch with big, legible numerals and illuminated marks. It was primarily designed for use by military pilots.
A pinion integrates with a wheel and an arbor to form a gear. A pinion has fewer teeth than a wheel and transmits motive force to a wheel. Pinion teeth, normally 6 to 14, are highly polished to minimize friction.
On a pin-pallet escapement, the role which would otherwise be played by pallet stones is played by steel pins which rise vertically from the plane of the pallet. These pins mesh with the teeth on the escape wheel.
A pivot is the end of an arbor turning on a jewel support. The pivots of the balance-staff are particularly thin and their shape and size can affect the amount of friction, which makes them fragile. Which is why they protected by a shockproof system.
Thin, galvanically applied layer of gold put onto the surfaces of watch cases that are made of non-precious metals.
Plastic crystals are soft and malleable this allowing it to be resistant to small impaves, enabling surface scratches to be buffed out.
Movement plates provide the housing for the inner parts of the watch and contain the jewels, pivots, and screw holes. The top plate, which usually contains the manufacturer signing name and serial number, can be easily seen by removing the back of the watch
A gold plated watch has a layer of gold "electrolytically" deposited onto the watch casing during the plating process. Goldplated watches usually have complex watch case designs which need a layer of gold deposited in tight recessed areas and contours.
Alternative word for Platinum.
The plating is normally a single metallic element and not an alloy. However, some alloys like brass and solder can be electrodeposited. Plated alloys are not true alloys like solid solutions, but rather discrete tiny crystals of the metals being plated. A lot of plating baths include potassium cyanide in addition to cyanides of the metal to be deposited. These free cyanides aid to anode corrosion, help to manage a constant metal ion level and contribute to conductivity. In addition, non-metal chemicals like carbonates and phosphates could be added to increase conductivity. There are times that plating is not wanted on specific areas of the substrate, so stop-offs are utilized to stop the bath from coming in contact with the substrate. The typical stop-offs include things like foil, lacquers, and waxes.
A precious metal regularly used in watch cases for its value and gorgeous properties. It has hypoallergenic properties as well, it's an expensive and effective way of avoiding wrist rash. Platinum doesn’t tarnish and consistently stays as radiant as it was new, which makes it one of the rarest and strongest metals. It’s one of the most prevalent choices for limited edition pieces.
A fabricated resin used for the watch crystal.
A pocket watch is a watch which was created to be carried in a pocket, as opposed to a wristwatch that is worn on the wrist. They were the most accepted type of watch from their development in the 16th century until wristwatches became popular after World War I. During the 1st world war which a transitional design, trench watches, were used by the military. Pocket watches typically have an attached chain to allow them to be secured to a waistcoat, lapel, or belt loop, and to prevent them from being dropped.
Distinction authorized by the Canton of Geneva to movements manufactured by watchmaker firms of the Region and acquiesces with all the standards of high horology with appreciation to craftsmanship, small scale production, working quality, accurate assembly, and setting. The Geneva Seal is engraved on at least one bridge and shows the Canton’s symbol. For example, a two-field shield with and eagle and a key respectively in each field.
The end result of the polishing process that creates an unblemished, high shine on a case/ bracelet.
Is a process used to make the case and bracelet smooth and brilliant by very fine-grained abrasives or by rubbing with a burnisher.
This term is in reference to the various tests performed on a watch to ensure its accuracy when held in one position.
This term is in reference to the various tests performed on a watch to ensure its accuracy when held in different positions.
Quartz watches do not utilize batteries, they use power cells. A battery is consists of one or more power cells that are joined together. Watches are small and need very little power as result only one power cell is needed.
A measure of how much energy is stored and hours of remaining running time in a watch movement.
The amount of time that a mechanical watch can work once it’s fully wound. A majority entry-level watches have a power reserve of approximately 40 hours, as opposed to many higher-end watches that can run for several days without being wound. Occasionally watches will have a power reserve gauge revealing how much the watch is wound.
A display on a watch that shows how much mechanical or electrical energy remains for the movement.
A feature of a mechanical watch that shows the remaining power in a watch movement, indicating the length of time until the timepiece will need to be wound again.
A timepiece that has a lever or chronometer escapement. A precision timepiece is assembled from high-quality components that includes an oscillating system that is able to take care of changes in temperature. Precision pocket watches and wristwatches will need a minimum of fifteen functional jewels.
This nickname is regularly used to describe the Rolex Day-Date models after the timepiece was given to then President Dwight D. Eisenhower in 1956, to celebrate his re-election. Now nearly every President since Franklin D. Roosevelt has worn a Rolex day-date model. The name ‘President’ is only officially used to describe the bracelet style featured on the Day-Date model.
Private Label watches also known as, promotional watches or logo watches, are timepieces that incorporates your own logo or brand name. Manufactured in Switzerland with over 30 years in the watchmaking business, our trusted supplier is a bonafide watch expert. They have been creating and producing watches of proven Swiss quality to provide a platform for worldwide famous companies since 1981. Virtually any idea can be implemented thanks to a broad spectrum of technicians and to their combined years of know-how. The name of the company, an image of the product, or, a companies logo can be carried out into the world in this impressive and elegant manner. These are normally given to those people who really appreciate and the company can be assured of providing a comfortable personalized high end luxury watch.
The word Prototype is derived from the Greek language. This term describes an original pattern or a model that serves as an archetype upon which versions created afterwards are patterned. A prototype is the first example of a watch and is usually crafted by hand before serial mass production begins.
A special scale that is found on a medical professional's watch that directly reads out a patient's calculated pulse rate as measured by the seconds hand. A scale on a chronograph watch which is used for measuring pulse rate.
See Pulsimeter
The pulsimeter scale displays the number of pulse beats per minute.
A button located on the side of a chronograph that helps to activate various functions that are available.
A button on a chronograph watch that helps performs multiple functions that when pulled out or depressed it starts, stops and/or resets the chronograph mechanism on chronographs have two pushers — one that starts and stops the mechanism and another button for resetting.
Mechanical element attached on a case for the control of specific functions. Normally pushers are utilized in chronographs, but used for additional functions as well.
Often referred to as buttons or push pieces. These are buttons only use on a watch is to start, stop, and adjust its various functions.
A push piece is an alternative name for a button on the side of the case.
An alternative to electroplating to provide a watch or its parts with a gold finish. PVD involves placing stainless steel parts in a sealed high-pressure chamber, where they are exposed to evaporated gold. Instead of plating the steel, the gold molecules are infused deep into the base metal's crystalline structure, resulting in a more durable 22k gold finish that is resistant to ultraviolet light, moisture, wear, and discoloration.
PVD plating is the process where by a coating of titanium nitrate is applied to the watch and then covered by a coating of gold to achieve a gold color finish.
A quartz watch is powered by a battery. The battery transmits an electric signal via a microchip circuit to a small quartz crystal that then pulsates at a precise rate. Those vibrations control a stepper motor that moves the watch hands. Quartz watches are more accurate, more dependable and cheaper than a mechanical watch. Mechanical watch fanatics don’t find them as appealing because of their simpler internal components.
The technical revolution found its way to the world’s wrists in the late 1960s. This was essentially a Swiss invention, The first working quartz watches were made by Girard-Perregaux and Piaget in a Swiss joint venture. However, it was the Japanese firms, chiefly Seiko, who was the first to recognize the advantages of the new technology and came to dominate the market. The quartz movement utilizes the famously stable oscillation frequency of a quartz crystal exposed to the electronic tension (usually 32,868Hz) as its norm. The Malvern Chronograph timepiece has the renowned Ronda Calibre 5040D, as its quartz movement.
A silicon oxide crystal, typically fabricated, with piezoelectric attributes. It's formed into small plates and when an electric impulse is applied, the crystal vibrates 32,768 times a second, allowing it to act as an extremely accurate resonator that makes even an economical quartz watch as accurate as the best mechanical marine chronometer.
A digital or analogue watch movement that utilizes a quartz crystal to keep accurate time. This is the most typical watch movement used today.
A movement powered by a quartz crystal, because they are very precise. They can be mass produced which makes them less expensive than a vast majority of mechanical movements which require a higher degree craftsmanship.
A movement that is powered by a quartz crystal where the crystal oscillates to power the timepiece.
A watch with quartz movement
Electronic wristwatches in which an oscillating quartz crystal serves as the regulating organ. The frequency of 32,768 Hz has become today’s de facto standard. Because the rate-regulating organ oscillates very rapidly, quartz timepieces are more precise than mechanical ones. Quartz wristwatches were first marketed in 1968.
Also known as Quick-Date, it is a mechanism to set the date directly to avoid having to turn the hands over 24 hours.
On a radial dial the minute markers are longer than the hour markers.
In 1978, a law about the determination of time (“time law”) was passed in Bonn which commissioned the Physikalisch-Technische Bundesanstalt (PTB) [Federal Physics and Technological Facility] in Braunschweig to “depict and disseminate the legal time”. Four highly accurate cesium clocks at the facility in Braunschweig keep time 100,000 times more accurately than the Earth does. According to law, the time kept by these clocks is transmitted from a long-wave transmitter DCF 77 in Mainflingen, near Frankfurt am Main. Anyone within 1,500 kilometers who has an appropriate receiver (a so-called “radio timepiece”) can use this time signal free of charge. The exact time, including the correct date, day of the week and month, are transmitted directly to the wrists of people who wear radio wristwatches. In the event of a temporary loss of transmitting capability, or if the recipient is outside the range of the signal, an ordinary quartz movement in the radio watch or clock can continue to accurately keep the time. As soon as the next radio signal is received, the displays on the radio timepiece are automatically synchronized with the norm time as transmitted from the cesium clocks in Braunschweig.
Corrected at regular intervals, by a radio signal transmitted from an atomic clock, often once per day. Radio-controlled watches utilize quartz movements within the timepiece. They work by picking up the radio signal by means of a small antenna inside their cases. In the United States, the time signal is broadcast by the National Institute of Standards and Technology from Fort Collins, Colorado. The atomic clock is itself located in Boulder.
Radium is a radioactive element that was used to illuminate watches by blending it with phosphorus and painting it either on the dial or markers. It was only phased out when it was discovered to be too radioactive to use on personal items.
This is a Rolex dial with "officially certified" and "superlative chronometer" centered so that the spaces line up creating a track-like look.
When a watch is fast or slow or does not have a consistent rate, especially in different positions, the balance wheel needs to be adjusted to compensate for the different positions. Although this too is a simple procedure, it does require a little more time to correct as each position needs to be monitored and adjusted. In rapid adjustment, the date can be moved forward or backwards between 23:00 and 03:00
Watch movements whose balances oscillate with a vibration number or frequency that has been accelerated to 28,000 or even 36,000 beats per hour in order to minimize their susceptibility to disturbances.
That being a flat ring with two raised tabs that act as the pawls against the ratchet on the underside of the bezel. If you have 60 teeth on the ratchet, 2 springs therefore giving a total of 120 clicks. When one spring is engaged, the other is between teeth in a semi-compressed state. Any unevenness between the sprung tabs and you get a slight difference in feel with every other click. The spacing between each click has been the same but they sound different. Its found that watches with one spring and 120 teeth on the ratchet provide a nicer feeling bezel. The caveat is "when it's done right".
A ratchet bezel ring can either turn one way (counter clockwise) or both ways and generally clicks into place.
The ratchet wheel sits on top of the barrel, and is attached with a screw to the barrel's arbor. When the ratchet wheel has been turned and has tightly coiled the mainspring the watch is wound. The click holds the ratchet wheel in place, so that the mainspring cannot unwind backwards. The clicking noise you hear when winding a watch is the click striking against each tooth of the ratchet wheel as it turns.
The rate is how accurately a watch is running, usually expressed in seconds per day. Each movement has an acceptable range of variability, and also a maximum deviation between extremes in all positions.
See “Split Seconds Chronograph”.
The addition of a flyback hand significantly increases the potential uses for chronographs. It allows the measurement of split-second times or timing simultaneous events of unequal duration
Also known as a split-second chronograph. A chronograph watch uses two seconds hands, the hands run together when activated, however one can be stopped independently to record laps and other events.
Also known as a double chronograph or a split-seconds chronograph, this adds an extra seconds hand and pusher to the standard chronograph function. The extra seconds hand moves together with the standard seconds hand, but stops when the extra pusher is depressed. Thus allowing the user to record two times at once.
When the split-chronograph mechanism is activated and the split-second push piece is depressed the split- second hand will stop, thus allowing the user to read the intermediate time, while the second hand continues to move. When the same push piece is pressed again the split second hand will catch up with the chronograph hand.
Some watchmakers would use their own nomination and should be crossed reference with standard ETA.
The register is another name for a sub dial that is usually found within the watch’s main dial. An example is a chronograph where there are registers for the chronograph minutes and hours. A few watches have registers with pointers that show the day and date.
see Regulator
The regulating organ of a mechanical watch is the balance with its balance spring.
Consists of a balance and balance spring that governs the division of time within the mechanical movement, ensuring regular running and accuracy. Since the balance works like a pendulum, the balance spring's function is made up of its elastic return and start of a new oscillation. This combined action regulates the frequency of vibrations per hour, and affects the rotation speed of the different wheels. In fact, the balance moves with its oscillations and at every vibration (through the action of the pallets), frees a tooth of the escape wheel. As a result of this action, motion is transmitted to the fourth wheel, which makes a complete revolution in one minute, to the third and subsequently the center wheel, the last-mention making a complete rotation in one hour. However, everything is decided by the correct time gap of the oscillations of the balance.
Also referred to as an Adjustment. Enhancing the timekeeping of a movement at various temperatures and in various positions. The regulation of most good quality watches is conducted in two different positions mainly dial up and crown up. Running discrepancies between the two positions typically do not exceed 30 seconds per day. Precision regulations in conformance with official criteria, such as those of COSC, a movement must be regulated in five positions and at three different temperatures (8°, 23° and 38° C). If the testing is actioned by an officially recognized institution and if the movement achieves or surpasses certain criteria, then the timepiece earns the right to bare the designation “officially certified chronometer.”
A piece of the movement that makes the time more exact by regulating beats by speeding them up or slowing them down.
A regulator separates the minute and hour hands onto different axial and sub dials. This allows the wearer to quickly tell tine without having to worry about the hands covering each other.
Monitoring the functioning of a movement by lengthening and shortening the active piece of the balance spring. Its marked positioned on the balance-bridge and encloses the balance spring with its pins near its fixing point on the bridge itself. By adjusting the index, the pins also are repositioned and by consequence, the portion of the balance spring capable of bringing the balance back is lengthened or shortened by its elastic force. The more concise it is, the more reactive it tends to be and the more quickly it brings the balance back and speeds up the movement. The adverse happens when the active piece of the balance spring is lengthened. Taking in today's high frequencies of functioning, even a small index shift entail daily changes of minutes. Not long ago, even more refined index-regulation systems were adopted from eccentric to micrometer screws to limit error margins to very few seconds per day.
A watch that has the ability to display the hours, minutes, and seconds and are read off of three separate and distinct subdials.
A different term for the inner reflector ring positioned just above the dial on all modern models. This area is now engraved with the watches serial number and the word Rolex repeated around the ring.
Remontoire from the French phrase, remontoir d'egalité, a device used to provide continual force to the escapement. Ordinarily, energy from the mainspring slowly decreases as a watch runs down, affecting accuracy negatively. The remontoire normally takes the shape of a spiral spring adhered to one of the train wheels, which is systematically wound up by the mainspring. As long as there is enough energy from the mainspring to wind it the remontoire spring will provide almost unvarying energy to the escapement. Remontoire springs can be rewound as frequently as once per second, or as infrequently as every five minutes or even longer. The spring remontoire was created by John Harrison for his marine chronometers. The older gravity remontoire, utilized in pendulum clocks, was created by the Swiss-born clockmaker, astronomer, and mathematician Jost Bürgi, by the end of the 16th century.
Thorough (final) control of a completed watch before it leaves its place of manufacture. Finishing also includes checking the watch’s rate. In the past, repasseurs (finishers) were the aristocrats among watchmakers.
A device that chimes the time upon pushing a slide lever.
A high-end complication that chimes to tell the time at the push of a button on the watch case.
A repeater is a watch which chimes when activated, typically by sliding a lever or pushing a button. There are several varieties of repeater, named by the smallest unit of time which their chimes indicate: quarter (of an hour), half-quarter (of an hour), five-minute, or minute.
A watch that indicates the time by a series of chimes when a button is pressed. Repeaters can sound on minutes, quarter hours or hours, depending on their design.
A copycat of another manufacturer's watch down to the logo, but openly sold as a fake at a drastically discounted price.
French word for Power reserve indicator
See Flyback
A watch that uses a crescent rather than a full circle of the dial to display the time. When the hands reach the end of the crescent, they instantly jump back to the beginning and start over.
An indicator on a watch dial that forms a piece of a circle, rather than a full circle. When the indicator moves through a full cycle, it automatically resets back to the zero position by moving backwards. Often used to indicate hours, minutes or dates.
A retrograde watch sets out the time in a linear format instead of the circular dial we are accustomed to. They move in an arc and them jump back to the beginning rather than the hands moving in a circle,
A watch that displays time in a linear manner instead of showing time in a circular fashion. In other words, the hands are not moving around in a circle; they travel along an arc. When they get to the end, they jump back to the beginning.
Described as a hand with a tip moving over a section of the arc instead of an entire circle. When it gets to the end of its path, it instantaneously returns to its point of departure.
Galvanic ennoblement applied, for example, to the surfaces of the movement. Rhodium plating can protect against tarnishing and give a bright gleam to surfaces. Furthermore, rhodium creates a harder surface. Rhodium can be refined from platinum ore, so it numbers among the metals in the platinum group.
A procedure by which a metal surface is coated with a thin layer of Rhodium. The main reasons for plating metal are: to enhance its appearance, and provide protection against corrosion.
Richemont owns several of the world’s leading companies. The Group’s luxury interests include several of the most prestigious names in the luxury watch industry including A Lange & Sohne, Baume & Mercier, Cartier, IWC, Jaeger-LeCoultre, Montblanc, Panerai, Piaget, Van Cleef & Arpels, Vacheron Constantin, & more. They collectively hold a private watch show every spring in Geneva for their Retailers around the world called SIHH.
South African founded company Compagnie Financière Richemont SA is based in Switzerland, Through its different subsidiaries, Richemont produces and sells jewelry, watches, leather goods, pens, firearms, clothing and accessories. Richemont is publicly traded as CFR on the SIX Swiss Exchange and the JSE Securities Exchange.
Hinged on a design completed in October 1982 by Breitling's CEO, Ernest Schneider. The rider tabs are a piece of the bezel. They have multiple functions, like being visual markers, grip aids (easy to use even with gloves), and also protect the domed sapphire crystal (which is glare-proofed both sides).
Rider tabs are four markers placed around the bezel used as points of reference to mark a departure time or a set time a user wishes to remember.
This was a bracelet used by Rolex in the 1950s and 1960s which was expandable, also known as a riveted bracelet.
Riveting systems, depending on the application requirements, can be manual or automated. All systems are very malleable in terms of product design and ease of integration into a manufacturing process.
Patented Rolex term meaning that there is stainless steel and Platinum on the same watch.
It is also referred to as “two tone” or “half gold/half steel” watches on other brands. It refers to the amalgamation of stainless steel and 18k various golds like 18k yellow, white or rose gold. The name Rolesor is a combination of the word 'Rolex' and the French word 'Or'.
Patented Rolex term meaning there is stainless steel and yellow gold on the same watch.
I, II, III, IV, V, VI, VII, VIII, IX, X, XI, XII
see California Dial
William Mosset (Founder of Ronda) was born in the village of Hölstein on 3 June 1909. He went on to complete his training as a precision mechanic in the same small settlement. It wasn’t long before William made his first invention. In spring 1929 he developed a tool that could punch 32 holes cleanly, precisely and simultaneously into a pillar-plate. He put his new expertise at the disposal of his then employer, but the invention also enabled him to found a company of his own. Ronda developed and brought to market over 30 watch movements, almost all of them highly complex, between 2000 and 2010. With its new Startech 3500 series, the company launched a further line of movements with stopwatch functions in spring 2011. At 23.90 x 25.60 mm, these are the smallest chronographs to date in the product range. As demand for mechanical watch movements continued to decline sharply, the company discontinued its production at the end of the 80s. After Ronda had strongly developed itself in various technologies and established a broad industrial basis, management decided to go back into the mechanical segment at the end of 2011. The 11½''' sized R150 caliber was introduced at “Baselworld 2016”, an in-house construction with three hands and date. The launch of the “Mecano” watch movement line is foreseen for the beginning of 2017.
A nickname for the brown and yellow bezels inserts for Rolex GMT and GMT II models.
A softly toned gold that has the same metals as yellow gold but with a bigger concentration of copper in the alloy. A popular color in Europe, rose gold in watches are regularly seen in retro styling or in tricolor gold versions. A few 18k red gold watches get their color from additional copper in the alloy.
By rotating the case, this watch can be set to two different times, allowing frequent travelers and those dealing with international colleagues in different timezones, the opportunity to remain abreast of different times. The two different dial designs offer two looks with just one watch.
A bezel that can be turned in either direction, clockwise or anticlockwise. Rotating bezels can be utilized for something as simple as marking elapsed time, or something as complex as turning the watch into a slide rule or a specialized calculator.
A rotating bezel is a bezel capable of being turned clockwise, counter clockwise or both.
A delicate cage, often made of steel. Titanium or aluminum are frequently used as the material for this assembly on modern wristwatches. On watches equipped with a tourbillon, this cage contains the oscillating and escapement system which consists of the balance, balance staff, balance spring, pallets, and escape wheel. The cage rotates around its own axis, usually at a rate of one rotation per minute. A rotating cage should be robust, interlaced, and as lightweight as possible. Crafting this assembly numbers among the most challenging and most laborious of a watchmaker’s tasks.
An asymmetrical, axe-shaped weight constructed to spin in reaction to a wearer's movements. This spinning action allows an automatic mechanical watch movement to be wound. Collectors regularly use automatic winders to power up watches while they are storage.
A piece of an automatic watch that winds the mainspring by constantly rotating.
An oscillating weight which is free to rotate through a full 360° circle and used on watches with automatic winding. Depending on its design, a rotor mechanism may wind the mainspring in either one or both of the rotor’s directions of rotation. One can distinguish between central rotors and micro-rotors. The former rotate over the entire movement; the latter are integrated into the plane of the movement.
A date wheel which shows the date in red and black numbers depending on if they are odd or even. Red for even and black for odd.
The gear train of a timepiece was first equipped with drilled rubies to minimize friction and wear by Fatio de Duillier and French watchmakers Pierre and Thomas Debaufre around 1700. The latter two watchmakers began manufacturing drilled and non-drilled jewels for watch movements in 1704. The first synthetic rubies were used in movements in 1902. The so-called “rubies scientifique” is hard and homogeneous, can be synthesized in whatever color one desires, and is relatively easy to process. It replaced the so-called “reconstituted ruby”, which is made by melting and pressing together fragments of waste ruby. Manufactured rubies differ from natural ones only in their genesis. The chemical composition of each is identical with that of the other.
Jewels serve two different purposes in a watch. The first purpose is to reduce friction as the reduction can increase accuracy. Second, they are used to increase the life of the bearings.
The entire running time of a mechanical movement, i.e. the interval between complete winding of the mainspring and stoppage of the hands due to insufficient energy in the slackened mainspring.
The Salon International de la Haute Horlogerie is a trade show held each year in Geneva. New model watches are unveiled for the trade and the show is not open to the public.
A crystal made of fabricated sapphire, which is see-through, but also slightly less hard than diamond, it is scratch and shatter-resistant. It is also more difficult to work or repair than some of the other available alternatives, like plastic.
Scratch-resistant material, having a hardness of 9 on the Mohs’ scale, used for watch glasses. Only diamond is harder than sapphire.
Every caseback in this category (Exhibition) has a part where the case material is removed and replaced by a “window” or sapphire crystal. That way the brand can expose his technical skills to us by (partly) displaying the movement to us watch geeks. This is also called an exhibition caseback.
Sapphire crystal is an extremely hard see-through material that is chemically the same as natural sapphire and ruby but without the other elements like iron and titanium that give the gem its color. Usually used for high-end watch crystals it’s manufactured by crystallizing aluminum oxide at extremely high temperatures until it measures 9 on the Mohs scale.
Sapphire crystals are 2-3 times more compacted than mineral glass and virtually scratch-proof. They are however more brittle and are more likely to crack or shatter than mineral. The cost to replace a sapphire crystal is substantially higher than for mineral crystals.
Sapphire crystals are made from manufactured sapphire and are virtually scratch-proof.
The sapphire crystal of a watch is scratch resistant, registering nine on the Moh scale, and is the material of choice for many watch collectors. The downside is that the sapphire can chip at the edges if it juts out it can shatter.
Mineral glass that has been toughened by a coat of sapphire to enhance its scratch resistance
Sapphirite glass is a toughened mineral glass coated with a layer of sapphire glass for extra durability.
The inner layer was Hardlex glass and the outer layer was Sapphire. It gives the scratch resistance of Sapphire with less brittleness.
A process that gives a fine, silky, matte polish given to metal surfaces.
Graduation on a measuring instrument, displaying the divisions of values, especially on a dial. The scales normally used in horology are associated with the measuring devices like tachometer, telemeter and pulsometer each performing a unique function. All of these scales start to measure at the beginning of the event concerned and stops at its end, the reading refers directly to the chronograph second hand, without needed further calculations.
See Crystal
A screw is a cylinder with a spiral thread and slotted head. Screws to secure two parts together in a way that is strong but can be easily removed.
The rear of the case has a thread so that it can be screwed into the case.
A crown that has threads screws down into the case to make the watch water resistant and to help keep out dust.
A screw down crown is a crown that is threaded and can tighten when the wearer screws it in. It uses a gasket that squeezes and seals the opening which makes sure it's resistant to water. This is a required element for any watch you intend on wetting.
Also referred to as a screw-down or screw-lock crown. This is a unique crown with screw threads and a gasket that allows it to be screwed into place, allowing the case to become watertight. When a user wants to wind or adjust the watch, the crown has to be unscrewed first. Since the threads are so small, special care must be taken when screwing it back in to prevent stripping of the threads.
A crown which screws down into a threaded barrel to help in the effectiveness of a watch's water resistance.
A case that allows the crown to be screwed into it to make the watch watertight. The time can be set by unscrewing counter-clockwise and pulling out the crown as instruction book indicates; following the adjustment, push and screw clockwise to tighten securely.
A crown that screws down into a case to make the watch more water resistant and to help keep out any foreign particles.
A seals purpose is to aid in water resistance and to keep out dust particles that could ultimately damage the watch resulting in expensive repairs.
Basic unit of time (abbr. s or sec), corresponding to one 86,000th part of the mean solar day, i.e. the duration of rotation about its own axis of an ideal Earth describing a circle round the Sun in one year, at a steady speed and in the plane of the Equator. After the Second World War, atomic clocks were so accurate that they could show the infinitesimal inconsistencies measuring even a few hundredths of a second per year of the Earth's rotation about its own axis. It was then decided to reevaluate the reference standard. This was done by the 13th General Conference on Weights and Measures in 1967 in the following terms: "The second is the duration of 9,192,631,770 periods of the radiation corresponding to the evolution between the two hyperfine levels of the fundamental state of the atom of caesium 133".
A sub-dial on a watch that keeps track of the local time within another time zone in either hours or a combination of hours plus minutes.
This indicator is an extra dial that can be utilized to set a separate time zone allowing the wearer to view two time zones at once.
Sector is an Italian wristwatch and diving watch brand.
Case back made of see-through material such as hardened mineral crystal which allows the main parts of the watch to be viewed while working.
See Automatic winding.
A hairspring made of an alloy that counterbalances for any ambient-temperature variations that would normally affect its rate. These self-compensating hairsprings, released under the name “Nivarox,” were introduced in 1933. Within a few years they rendered the elaborately constructed bimetallic balances, which had until then been used to counter the effects of temperature change, obsolete.
Sellita is a Swiss movement manufacturer and largely manufactures part copies of ETA movements. It does this because it has the machinery capable of such work, along with the fact that the ETA designs are old enough to be likely to not be protected under any Patent rights. This is the reason Sellita can make copies of ETA movements just like drug companies can make generic drugs after a period of time. The Sellita SW200 movement in a watch is the same movement as an ETA 2824-2. The reason watchmakers are using Sellita movements is not so much about cost, but more having to do with the fact that ETA is slowing down production and will cease to provide movements to watchmakers outside the Swatch Group in 2010. So because ETA movements are harder to get, watchmakers will use an ETA or Sellita movement depending on what they are able to acquire in time to put the watches together.
This is a unique number issued by a manufacturer and is usually engraved on the outside or inside of the caseback or between the lugs.
Serial winding is the winding of an electric motor or generator in such a way that the field and armature circuits are connected in series,
Servicing or overhauling an entire watch movement is the most simplest form of watchmaking. A technician totally disassembling the watch mechanism which includes cleaning the parts, oiling the proper places, then re-calibrating the watch to keep good time. A simple overhaul does not include repair but rather be thought of as a thorough cleaning.
Circular piece of metal stamped with a hole to accommodate a jewel. To affix the setting to its bar (bridge), it is either pressed or screwed into the bar. The original purpose of the setting was primarily an aesthetic one. Crafted from gold or a metal similar to gold, settings were used to enhance the shine and effect of beautiful jewels. Only later did watchmakers discover the pragmatic usefulness of settings. The jewel inside a factory-made setting can be readily replaced if the stone should break. In the wake of the automated manufacture of watch movements, settings became increasingly more common. Stamps could very precisely punch holes into the bridge to accept the settings. Settings become useless after jewel manufacturers became capable of delivering their products in thoroughly impeccable quality and exactly identical size. These jewels could be pressed directly into holes drilled in bridges, cocks, and plates. Screwed settings are utilized today as they have a attractive appearance. They are most often found in movements made by watch manufacturers in Glashütte.
The word derives from the French "chagrin" and is derived from the military and trade navy vocabulary of the 18th century. To go to the chagrin meant to clean the merchant ships deck with a piece of very rough shark dogfish skin not unlike sandpaper). For that time, Chagrin or Shagreen meant the use of only the shark dogfish leather. Afterwards, the leather of Sephen ray, a pelagic ray from North of Indian Ocean, was also used (as the leather of shark dogfish) in furnishing or small objects sheathed. The shagreen word stood for leathers of these both animals.
A watch movement which is not circular in shape. A varied array of differently shaped movements (e.g. tonneau shaped, baguette shaped, rectangular) have been developed, especially for use in wristwatches. Shaped movements have become quite rare in todays watches.
A shock absorber is nothing more than a very hardy bearing in a watch that is intended to take up the shocks received by the balance staff and protect its delicate pivots from damage.
A shock absorber is nothing more than a very hardy bearing in a watch that is intended to take up the shocks received by the balance staff and protect its delicate pivots from damage.
System to protect the fine and therefore very delicate pivots of the balance staff against breakage. To accomplish this, the bearing jewels and endstones in the balance staff’s bearing are elastically affixed to the plate and balance cock. When the watch is struck by a hard blow, these jewels give laterally and/or axially. A watch with shock absorption should be able to survive unscathed a fall from one meter’s height onto a wooden floor. After the plunge, the watch’s rate should not exhibit any major deviations. Watches with shock absorption systems were first marketed in the 1930s. Shock absorption had become standard equipment by the 1950s. Originally, many watch brands utilized their own shock absorption systems (partly to reduce costs), but these systems did not survive in the long run. The best-known and most widely disseminated shock absorption systems are the so-called “Kif and Incabloc” systems. The latter can be recognized by its steadying spring, which is shaped like a lyre.
An official measurement of how a watch can tolerate impacts without suffering severe damage. The US standard is an impact proportionate to being dropped from three feet (1 m) onto a wooden floor.
This is defined by the watch’s ability to tolerate an impact equal to that of being dropped onto a wood floor from a height of 3 feet.
A watch’s ability to endure an impact equal to being dropped onto a wooden floor from a height of 3 feet
A timepiece which measures and supports the immediate reading of the duration of brief intervals. By definition, such devices include stopwatches and chronographs.
The time of the Earth's rotation as measured from the stars. Measures approximately 3 minutes, 56 seconds shorter than the mean solar day.
Sidereal time is a timekeeping system that astronomers use to uncover celestial objects. Using sidereal time, it is achievable to easily point a telescope to the correct coordinates in the night sky. Summarily, sidereal time is a "time scale that is based on Earth's rate of rotation measured relevant to the fixed stars
In watchmaking, sideshake is defined and measured by the extent of play a pivot has in a jewel-hole. A little bit of side-shake is necessary in order for a gear to turn, but excessive shake is undesirable as it can cause gear teeth to bind and stop the watch. Causes of excessive side-shake include wear of pivots due to them running in dry or poorly lubricated jewels.
A Sigma dial is actually a Rolex dial named for the letters printed at the bottom of the dial at 6 o'clock position. A majority of Daytona dials are embossed with “T Swiss T,” however a Sigma dial is marked “σ T SWISS T σ.” The Daytona's name is derived from the name from the two O shaped symbols on either side of the T SWISS T.
This metalloid is growing more and more common in watchmaking (mostly in balance springs and escapements), as it does not react to changes in magnetism and temperature like metal does and does not require lubrication. Watches with these silicon components are often a lot more accurate, more reliable and more resistant to magnetism than watches that use metallic components.
A cost-effective metal compound that closely resembles actual silver.
Similar to an exhibition case back, a skeleton watch showcases the inner workings of the watch. It achieves this via a transparent or partially cut-out dial so that the movement can be seen from the front of the watch.
A case created to showcase the internal mechanism of a watch. This can also include using a crystal set in the back of the case, special skeletonized components, and even cases made entirely of sapphire.
A skeleton watch is a mechanical watch that showcases the moving parts via the front of the watch via a small cut that outlines the dial. Genuine skeletonization includes the removal of any extra metal on any mechanical part of the watch thus leaving only the bare skeleton of the movement required for functionality. Generally, the remaining thinned movement is embellished with engraving. This can include or exclude a dial face that allows permits the user to see through to the movement.
Watch hands that are solid with cut out centers are known as skeleton hands.
A watch movement whose plate, bridges, cocks, barrel and sometimes also rotor are pierced so that the only material which remains is that which is absolutely indispensable to the function of the skeletoned component. Elaborate piercing makes it possible for one’s gaze to penetrate deep into (and sometimes through) the movement. Skeleton work is manually executed and requires a highly skilled watchmaker. The quality of the craftsmanship is most easily recognizable in skeleton work at the junctures where faceted edges meet. Three different kinds of corners can be differentiated: 1. The inset corner. Two facets meet to form an inset corner. The junction should be a perfectly straight line connecting the points of intersection of the two edge lines. This type of corner, which can only be created by hand, proves that the skeleton work is of the very highest quality. 2. The protruding corner. The juncture of two facets forms a protruding corner. This corner will have a sharp edge and should be neither blunt nor rounded. 3. The rounded corner. Unlike the two preceding forms, the facet here does not have a sharp edge. Rounded corners are less artful and less valuable than the other two types of corners because machines can also be used to create them. Wristwatches with skeleton movements debuted in the mid 1930s.
Watches where the bridges and pillar-plates are cut out in a ornamental fashion, therefore revealing all the parts of the movement.
A combination of the case, dial and various other parts of the movement have been cut away showcasing the main parts of the watch. A crystal is positioned and attached on both the front and back of the watch.
One of the favorite styles of watch casings, a skeleton watch is a case with no dial that has a transparent front that allows the wearer and admirers to view the movement without removing the watch.
Skeletonizing existing movements is an exercise riddled with difficulties. Skeletonization is a way for watchmakers to express their brand identity and showcase the beauty of their calibers
A movement where the plate, bridges, cocks, barrel and rotor (if present) have been pierced so that only essential metal for each part’s function remains. Skeletonized parts make it possible to look into and sometimes through the movement
A rotating bezel that can multiply, divide numbers, convert miles/KM, convert exchange rates, etc. An example is a dollar to Euro converter to calculate the rate of descent or fuel consumption for pilots.
This is in essence a navigation computer that consists of a scale on the outer edge of a watch face allowing the wearer to perform mathematical calculations such as fuel consumption or converting miles into nautical miles or kilometers
A bezel created to perform various mathematical calculations, including multiplication, division, speed over a fixed distance, fuel consumption, and others.
Governing device for a chronograph. A moveable cam, the shape of which varies depending on the particularities of the caliber, provides the “programmed” information for the chronograph’s start, stop, and return-to-zero functions. Chronographs with a slideway or cam governing are less complex, but no less reliable than chronographs with column wheels.
The time display in where the second hand is placed in a small subdial.
This is the smaller of the typical three hands found on a watch, namely the Hour hand, minute hand and seconds hand.
A small sub-dial separate from the hour and minute function that shows the seconds.
The seconds are shown by a hand in a small subsidiary dial and not from the center of the timepiece.
A computerized watch created to act either on its own or when paired via Bluetooth with a mobile device. The crystal of the watch acts like the touchscreen of a smartphone, and the watch can carry out a wide variety of functions.
A smartwatch is a highly technical wristwatch, which is actually more of a wearable computer. The latest smartwatches provide a local touchscreen interface for that can be easily accessed. The watch can be connected to an associated smartphone app which provides for management and telemetry.
A small cam that regulates a movement's functions, especially in chiming watches.
Embellishments with a spiral pattern, typically used on the barrel wheel or on big-sized full wheels
A solar wristwatch uses sunlight or man-made light captured by a solar panel to power the timepiece. It does not require a battery or daily winding. These watches incorporate many functionalities that are also solar powered for example a Digital compass, altimeter, thermometer etc.
A quartz watch that uses a photovoltaic cell set in its case or dial to keep the battery charged by converting ambient light into electricity.
Just as they sound, these batteries are found in a quartz watch and are recharged using solar panels found on the dial
A solar wristwatch utilizes sunlight or man-made light stored by a solar panel to power the timepiece. Unlike your normal timepiece, it does not require a battery or daily winding. These watches not only work when there is sun but uses the stored energy to operate at night. Men’s and woman's solar watches have been mass produced since the beginning of the 1970s, with technology progressing to the point where a few watchmakers offer solar timepieces as their primary watches. Solar watches are designed to be contemporary and typically have multiple functions. Solar watches are very tough and quite a few feature stainless steel or titanium cases and hardened mineral or sapphire crystals. Some have a blue-grey tint on the dial, which is designed to get the most out of sunlight. Many solar watches accentuate their ruggedness by adding on functions like a stopwatch, Multiple time-zone displays and the ability to be water resistant up to 200 meters.
Solar-tech is the technology of using photovoltaic solar cells within the watches that are manufactured with this technology. They use an ultra-small solar panel on the face of the watch to generate electrical power from sunlight for its rechargeable battery. Tough Solar tech can also generate power on cloudy days or under fluorescent lighting – although charging speeds will obviously differ depending on the light source.
The Tough Solar System is now so progressive that even the most feeble light sources are enough to operate the watches. The solar cells are so small and concealed so well that they can be integrated easily into every watch face design. CASIO's solar field can also be created in any color and design the wearer desires. A gatherer in solar watches saves "superfluous" energy and discharges it when the watch is in darkness. Solar watches always have an accumulator built in. The accumulator does not require manual activation as it is charged automatically.
A variety of minute repeater that sounds the time systematically on every hour (petite sonnerie) or quarter hour (grande sonnerie).
A function made up of an acoustic sound that's obtained by a work made up of two hammers striking gongs at set hours, quarters and half hours.
A collector’s term referring specifically to glossy black dial, usually submariners, the dial cracks and splits leaving a spider web pattern in the lacquer.
Having the form of a spiral. See also: balance spring.
A second hand on the second spring. Can be stopped independently of the switched-on chronograph and return to the current time with the push of a button.
Can be classified as a very brief moment of time. The split-seconds chronograph is used to time different events that begin but do not end together.
An extra hand is superimposed on the chronograph's hand, and by putting pressure on the pusher starts both hands, which remains superimposed as long as the split second mechanism is not blocked. After the recording is completed , the same pusher is pressed a second time, releasing the split-second hand, which immediately joins the still-moving chronograph hand. Thus, synchronizing with it to prepare for another recording. This type of function is particularly useful for timing simultaneous phenomena which began at the same time, but end at different times.
This refers to two hands - a flyback (rattrapante) hand and a regular chronograph hand. Both hands move together but, to time laps or finishing times, the wearer can stop the flyback hand while the chronograph hand continues. This, in effect, splits the hand in two.
A watch that has two hands so that one of which can be stopped to indicate an intermediate time while the other hand continues to run.
This is a more intricate chronograph consisting of two center seconds hands. The extra hand has the functionality to be stopped independently while running at the same time as the main hand. It can also be made to catch up with the running chronograph which is why it’s called a “split seconds hand”.
Also referred to in the watch industry by its French name, the rattrapante. A watch with two-second hands, one of which can be stopped with a special dial train lever to show an intermediate time while the other hands continues to run. When the hand is released, the split-seconds hand jumps ahead to the position of the other second hand. The C3 Malvern chronograph and C4 Peregrine chronograph have this useful function.
See Rattrapante.
A spring-loaded metal bar mounted between the case lugs utilized to affix a strap or bracelet.
These are spring-loaded pins located between the lugs and used to attach the bracelet, band or strap to the case.
The spring barrel contains the mainspring. It turns with ease on an arbor that's been pulled along by the toothed wheel typically doubling as its lid. This wheel interacts with the first pinion of the movement’s gear train. A few select movements contain two or more spring barrels for added power reserve.
Also known as spring bars or pins. Spring-loaded pins that run between the lugs on a watch case, that are used to attach a strap or bracelet.
See Stem
A highly durable, corrosion resistant steel/chromium alloy. It's metal of choice by many watchmakers not only for its hardness and durability but also for its ability to take on a very bright shine that does not discolor or wear off. It's often used for cases, case backs, and bracelets.
A very durable metal that is not only rust but corrosion resistant as well. This material is normally recommended to who can’t afford a precious metal such as solid gold or platinum but still want something that looks nice.
Standard time is considered to be the time that is kept locally in each of the time zones when it is not daylight savings time.
The crown is fitted on the opposite end of the shaft that connects to the movement’s winding mechanism.
This is a part of the analog movement in a quartz watch that moves the gear train which turns the hands on the dial.
Sterling silver is a precious metal that is 92.5 percent pure. The silver fineness is stamped on the metal, accompanied by the initials of a designer or the country of origin as a hallmark. A protective coating is sometimes added to prevent tarnishing.
A copper/silver alloy that has at least 92.5 percent purity silver. It's often used to manufacture watch cases and bracelets, but is prone to tarnish if not kept polished.
Another word for a chronograph.
A mechanism that halts the movement to allow time to be synchronized to a time signal with to-the-second precision. To achieve this, the wearer pulls the crown out the instant the seconds hand reaches the “12.” When the user hears the time signal, he immediately pushes the crown in and the watch starts running again. This is also called a “hacking” feature.
A specially designed watch that record time in intervals down to a fraction of a second. It can also be referred to a specific function on a chronograph watch.
A traditional device that is now obsolete, provided with a finger piece attached to the barrel arbor and a small wheel in the shape of a Maltese cross mounted on the barrel cover, thus limiting the extent to which the barrel can be wound.
A surface finish that is achieved by rubbing an abrasive on a workpiece in a linear fashion. Often used for springs and bridges.
A strip or band that can be made of leather or rubber that holds the watch to the wrist. It has to be manufactured out of non-metal to be considered a strap. A metal version of this is referred to as a bracelet.
The watch strap is typically made from materials like leather, rubber or a fabric such as nylon. It's used for the same purpose as both the bracelet and band.
See Sonnerie and Repeater.
Also subsidiary dial. A miniature dial set in the main dial of a watch to register information like hours, minutes, seconds, other time zones, day, date, or power reserve.
A small dial placed within the main dial of a watch. Watches can have as many as four auxiliary dials. They relay information not given by the main watch dial such as chronographs, alarm, dual time zone, and calendar.
A small dial on a watch face that can be used for any of a variety of purposes, such as keeping track of elapsed time on a chronograph or indicating the current date.
Sub-seconds is a placement of the second hand not in the center of the dial. In this type of configuration, the seconds hand is typically attached directly to the fourth wheel.
The sub dial is an auxiliary dial used for various purposes and functions.
Different to center or sweep seconds, a small subdial showing seconds, typically at 6 o'clock.
An additional complication found on watches, it is a wheel that is partially visible through the dial indicating the sun and moon in a 24-hour period.
Rolex developed and patented the super balance in 1935. The steam lined balance wheel improved the functioning of the auto rotor movement.
The Superlative Chronometer certification has checks to guarantee the key areas of performance that can be disrupted during the manufacturing process. These key performances include precision, power reserve, waterproofness and self-winding.
Christopher Ward watches use Super-LumiNova, a photo-luminescent non-radioactive material with a long period of phosphorescence. It goes up to more than 100 times the brightness of Tritium. Tritium was the original, radioactive, liquid used to coat hands, numerals and hour markers on watch dials to make reading the time in the dark possible.
A quartz watch that incorporates self-charging technology with solar cells of Kinetic drive. They suffer the drawbacks of obsolescence and difficulties in servicing.
A seconds hand that is seated in the center of the dial. The sleekness of the seconds hand, whether it moves in a series of ticks or in a single, smooth motion is an indication of how many vibrations per hour the movement generates.
A center second hand, is a second hand seated on the center of the main dial
On a quartz watch, the second hand has the tick tick motion that moves once per second while mechanical watches have a smooth and sweeping movement.
A second hand that is attached in the center of the dial, and sweeps the entire dial of the watch.
A mark or origin, this label shows that the watch was put together in Switzerland and that the components are Swiss made as well.
A hallmark certifying that a watch is a genuine Swiss made.
The Swiss Lever escapement has been the standard in horology for hundreds of years. The escapement provides the release of energy from the mainspring to the going train that further controls the function of the moving parts that measure time and other complications. The Swiss lever, although the mainstay in the industry, has the capability to be strong on energy conservation but needs considerable lubrication between the impulse pallet and the escape wheel teeth due to sliding friction.
A watch can only be considered to be Swiss made if, it has a combination of the following, its movement is Swiss; its movement is cased up in Switzerland and the manufacturer does the final inspection in Switzerland.
Swiss Movement as commonly stamped on watches should not be construed as being Swiss Made. In order to label a watch as Swiss Movement, only the movement must be made in Switzerland, where the remainder of the watch, its casing and its components can be manufactured, assembled, and inspected anywhere else in the world.
An official designation for a watch that has a movement made in Switzerland that contains at least 50% Swiss-made parts and is inspected and assembled in Switzerland
Is a wristwatch show hosted by The Richemonte Group with the assistance of differentluxury watch brands. The first SIHH show was held in 1992, featuring 5 different watch brands. It is currently held every year in Geneva. SOme of the brands the attend the show are Audemars Piguet and Rcihard Mille.
It's headquarters is in Switzerland. Has an estimated sales revenue of over $8 billion a year, as of 2021. The company was created in 1983 and made as a private company in 1985 by Nicolas Hayek, who was CEO at the time.when it renamed itself after taking over the operations of ASUAG and SSIH. In 1986 it was named SMH (Societe de Microelectronique et d Horlogerie SA). Then in 1998 it was renamed again to the Swatch Group. The Swatch Group produces watches and also owns many different watch brands. Some of these brands are Blancpain, Breguet, CK Calvin Klein, Hamilton, Harry Winston, Longines, Omega, Swatch and Tissot, just to name a few. Stephan Schmidheiny and Esther Grether were some of the main investors.
A tachometer, also known as a tachymeter, is a addition on dial of a chronograph which allows a user to determine average speeds or hourly production on the basis of an observation period of under sixty seconds.
Also called a tachometer. A graduation found on some chronographs that calculates the speed of a vehicle after it travels a measured mile or kilometer. The seconds hand is activated as the vehicle starts the mile and stopped when it completes it. The readout on the dial is the speed.
A notably regular feature in chronographs, the tachymeter measures speed over a specified distance. The user will start the chronograph at the starting line and stop it when finishing.
Conventional feed through buckle similar to that of a belt buckle.
A watch strap that resembles and can be used like a belt buckle.
A tang buckle is the most common strap found in todays market it consists of a traditional loop and pin and resembles a belt buckle
The Tank Watch is a rectangular luxury watch designed by Cartier. The name is derived from its resemblance to the treads on an army tank.
Tantalum watches are exceedingly rare and for a good reason. They feature a characteristic blue hue that hides beneath the lustrous silver overtones, tantalum often provides watches with a stealthy luster that other metals fail to achieve, even metals like titanium
A Vertical ridge design that covers the entire dial. There were many different colors and patterns available, however, this has now been discontinued.
A function similar to a tachymeter, only it measures the distance sound travels rather than vehicle speed by tracking the difference between a distant event and the arrival of the sound associated with it.
To improve the hardness and elasticity of steel or other metal, by the process of reheating and then cooling it.
A rectangular watch that is adorned with heavier bars on either side of the dial. The design is inspired by the tank tracks of World War I and was first created by Louis Cartier.
Quartz watches split time by manipulating the electromechanical anomaly known as Piezoelectricity. The quartz crystal starts resonating at a constant frequency when a continuous electrical current runs through it. Crystal oscillators for watches are created to vibrate at 215Hz (32,768 Hz), a frequency that will be halved 16 continuous times by a processor to get the second unit of time. The issue with quartz crystals is that they are easily afflicted by temperature and they tend to vibrate faster in heat and slower in cold. As a repercussion, quartz watch can have a -10 to +15 sec. variations per month. Keeping this in mind, the quartz oscillator is still far more accurate than the anchor escapement found in mechanical watches. The solution ETA engineers discovered was to put in a thermometer that will constantly feed information to the processor, allowing it to compensate for errors caused by temperature. Movements using this technology can be correct in the range of -10 to +15 sec. per year. This move by Christopher Ward to use a super-accurate quartz movement and to get it certified shows their commitment to using the best movements available for their timepieces.
A miniature built-in thermometer measures and displays temperatures throughout the range from -10°C ~ 60°C. This is found in a variety of watchers and is ideal for users that go hiking, diving or any outdoor activity where the temperature reading is needed.
The third wheel sits between the center and fourth wheels. It makes it possible for the large increasing gear ratio of 1 to 60 when considering the gyrational speed of the center and fourth wheels.
Unlike bridge-type movements, nearly the entire gear train (with the exception of the pallets, escape wheel, and balance) is borne beneath an additional plate. Three-quarters plates are utilized in American and English watches and also in watches that are made in Glashütte.
Refers to a simplistic, yet luxurious watch who's crown is pulled out to 3 different positions to set the time and date.
This is a bezel designed by Rolex for the Rolex Datejust Turn-O-Graphs. They were used by the U.S. Airforce Thunderbirds.
This shows high and low tides for your area. Calculated using the current time, GMT setting, Latitude and Longitude, and the Lunar Tidal Interval.
Time zones refer to the twenty-four regions or divisions of the globe. They are normally displayed in UTC.
A common term for a complication that logs intervals of time. If it goes forward, it's a stopwatch or chronograph, if backwards, it's a countdown timer.
A metallic component known for its strength and lightweight – both of which exceed that of stainless steel. It is hypogenic and has a pleasing greyish sheen. However, it is very difficult to work, so its application in watches is limited.
A tongue, or tang, is a movable metal piece in a buckle which penetrates the holes in a leather strap
Part of the frame that the strap gets put through before putting the tongue through the hole is often referred to as the end bar. The center bar holds the tongue and the part that holds the tip of the strap in place is called the keeper or the keeper bar. These terms are used when extra information is required to describe a buckle for measurements or design.
A watch that is designed in a barrel like shape with two convex sides.
The name for a particular case shape used in watches, with rounded edges and bulging sides, resembling a barrel or a cask.
The word tonneau is the French word for barrel, and the overall profile of a tonneau is a rectangle-shaped case with rounded corners and bowed-out edges which looks, in fact, barrel-like. So the tonneau is a close relative to the cushion case, but the overall shape is taller and longer. On dress watches, this gives the timepiece some art decco vibes, though the style was exceedingly common on chronographs and dive watches from the late ’60s and early ’70s.
A watch made to carry out a practical task other than basic timekeeping to support a specific occupation, like scuba diver or pilot.
The totaliser is a mechanism that tracks elapsed time and is commonly referred to as a sub dial.
See Totaliser
See Tonneau Case
A device that eradicates errors in timekeeping by balancing the horizontal and vertical positions of the balance wheel.
A type of escapement enclosed in a revolving cage that is meant to counter the negative effects gravity on a movement. This type of movement was originally developed for pocket watches, they have ve moved to wrist watches as a way to display the height of a manufacture’s watchmaking abilities, and as such, they expect exorbitant prices.
This has been characterized as the most popular, yet useless complication on modern mechanical watches. It was originally created for pocket watches, which spent their time either sitting upright in a man's waistcoat or other pockets or lying flat on a dresser at night. This introduced the gravitational effect as it was typically in only one of two positions. The tourbillon was included into the watch escapement to eradicate this effect by turning in every direction in a small, revolving cage. Wristwatches made the tourbillon are discontinued because a watch on a wrist is constantly shifting position, cancelling out gravity, but it's still included in modern watches because it's impressive to look at.
In a watch , the train comprises a wheel whose teeth mesh with a pinion 's leaves and is a system for transmitting power and motion through toothed wheels.
This is a very rare bracelet made by Rolex using three shades of gold (yellow, rose and white). This is found on some of the Rolex Day-Date models.
A watch with a triple date complication tracks the date (numeral), day of the week (Monday-Sunday), and the month of the year. Unlike a perpetual calendar, these watches will need to be manually adjusted at the end of every month with fewer than 31 days
A watch stamped on the case, dial and movement with the manufacturer's name or trademark is said to be Triple Signed.
A winding crown system which has a triple seal against water and dust, created by Rolex.
A gaseous radioactive isotope of hydrogen used to illuminate watches by sealing the gas in tubes painted with a phosphorescent material. These tubes can provide light for up to 25 years, but do not have the dangerous radiation of earlier radium watches.
A substance that is slightly radioactive that collects light and is utilized to permit the hands or hour markers to illuminate in the dark. The radiation is at such a low level that there is no health risk. Watches market with the letter T, found by the 6 o'clock mark' shows that tritium has been used.
Tritium is used in radioluminescent light sources for watches which will allow the parts to glow in the dark.
A term referring to a specific dial patina usually on matte, black, professional models with the color turning a dark brown.
An electronically excited tuning fork, oscillating at a frequency of 360 Hz, serves as the regulating organ. The best-known tuning fork watch is Bulova’s “Accutron”, which debuted in 1960.
Decorative engraving, usually on the watch face.
A watch with two crowns with one for adjusting an winding the movement and the other to control some other function, like a rotating bezel mounted inside the crystal.
A winding crown system which has a double seal against water and dust, created by Rolex.
Two tone is used to describe a watch or bracelet that blends two contrasting metals or metal platings, like gold and stainless steel.
Ultra-thin refers to a watch that appears proportionately slim when looking at the case profile. There are no official dimensions for what constitutes "Ultra-thin" at this point.
A silver underscore which appeared under "Rolex Cosmograph" in 1963 Daytona models. It is believed that this was done to show the watch contained Tritium as opposed to the radioactive radium that had been used in the past.
A bezel that indicates the time that has gone past which is a function commonly found on divers watches. It moves only in a counter-clockwise direction. If a diver is monitoring the air supply he has left and knocks the bezel by mistake, it will only move in one direction so that the error will only be on the side of safety.
A bezel that is designed to only move in an anticlockwise direction It's utilized on a diver's watch to track elapsed time in minutes. The advantage is that if the bezel is accidentally moved, it can only result in making an overestimate of the time underwater, which is not a dangerous mistake.
Mean solar time for the Greenwich meridian, but counted from noon to noon.
Greenwich Mean Time (GMT) but is now known to as Coordinated Universal Time or Universal Time Coordinated. It is a coordinated time scale that is maintained by the Bureau International des Poids et Mesures. It is also be referred to as Z time or Zulu Time.
Movement of the oscillating piece of the watch, limited by two extreme positions. Generally 5 or 6 vibrations per second, 18,000 or 21,600 per hour, but can also be a higher frequency with as many as seven or ten vibrations, 25,200 or 36,000 per hour. See also: Frequency.
The sum of the beats of the rate-regulating organ (e.g. pendulum or balance) of a timepiece is described as its “vibration number”. One full oscillation consists of two sequential vibrations. Examples include classical wristwatches that generally have an oscillating frequency of 18,000 vibrations (or “beats”) per hour. In other words, the balance completes 9,000 oscillations (beats) or 18,000 half-oscillations (vibrations) per hour. The frequency of the balance of such a watch is 2.5 hertz (Hz).
The VPH is the movement of an oscillating part that is limited to two extreme positions.
A timepiece
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Watch winders were developed to copy the movement of your wrist, by slowly rotating an automatic wristwatch in a stationary position to keep it fully wound. If an automatic wristwatch is on a watch winder, its power reserve will not run down and it will not have to be reset. Not all watches benefit from a winder, for example, a quartz or manual-wind movement.
A watch winder is a machine that automatically winds your watches when not in use.
The capability of a watch to resist splashes of water on the timepiece. This will display the depth that a watch can be worn underwater.
Watches that display that they are water resistant can withstand the effects of water to a very limited extent. It’s essential to check the manual and warranty to ensure you don’t overestimate its resilience. It’s also necessary to remember that as a watch ages the resistance to water is decreased so it’s best to check it annually.
Another term for waterproof obsolete term for water resistant. It was discarded in the watch industry because it was ruled to be misleading and, therefore, illegal to claim.
An official classification for a watch case's ability to tolerate water pressure as measured in depth as marked in meters, feet, or atmospheres.
A circular component that's mostly toothed, amalgamates together with an arbor and a pinion to make up a gear. The wheel turns around an axis and its purpose is to transmit power or motion. Wheels are normally made of brass, while arbors and pinions are made of steel. The wheels that are between the barrel and escapement make up the so-called train.
Also referred to as the Going Train. The series of wheels and pinions that carry power from the mainspring to the escapement while, driving the minutes and seconds hands (the hour hand is driven by the watch’s motion works) at the same time. The front wheel in the wheel train is the mainspring barrel. The other wheels are known as the center wheel, third wheel, fourth wheel and escape wheel with each one that has an accompanying pinion that drives the next wheel in the train.
Wheels and pinions comprise the gear train. Wheels are large gears usually made of brass and pinions are small gears usually made of steel. They are riveted together when used in a gear train.
A metal alloy of gold blended with nickel or palladium to give it a silver or platinum-like color. Devised from yellow gold by mixing either nickel or palladium to the alloy to achieve a white color. A majority of watches made of white gold will be 18k.
A box or case or vault if you have the means that gently winds an automatic watch to keep the mainspring fully wound when it isn’t being used.
Winding is the process of tightening the mainspring of a watch using a crown, key or automatic rotor.
Tightening the mainspring. This could be manual or automatic.
The winding stem is the section between the exterior and interior of a watch. The process of winding the stem by turning, pulling, and pushing the crown winds and set the mechanical movement. The crown is attached on the threaded end of the winding stem. The threaded side is measured and cut to length that is required depending on the size of the case. The other side of the winding stem has a square, which interfaces with the winding and setting mechanisms in the movement. There are pivots on the end of the square stabilizes the winding stem as it turns.
Aperture in the dial that permits reading the underlying indication, mainly the date, but also indications of a second zone’s time or jumping hour.
An extra feature of watches provided with a GMT function is showcasing the 24 time zones on the dial or bezel. Each zone is referenced by a city name thus providing an instantaneous reading of the time of any country.
A sophisticated complication that displays the time of up to 24 different time zones. These watches are often referred to as World Timers.
A complication that shows the time in zones from around the world. This is displayed in one of two ways, a dial marked with the names of cities in each of 24 time zones or a hand that marks the time in Greenwich and a 24-hour rotating bezel for calculating the time in the place the user requires via addition or subtraction.
Beginning at zero degrees longitude (i.e. the Greenwich meridian), the time differs by one full hour with every 15 degrees of longitude. The world’s system of time zones was first introduced by Canada and the USA in 1883. Germany began to comply with this system in 1893. Watches with world time displays may show up to as many as 24 time zones on a single dial. An additional mechanism supports the simultaneous display of the time in more than one-time zone. (A so-called “heure universelle” may display the time in as many as 24 different zones.) Watches with world time display have been available since the 1930s and are particularly useful for people who fly on long-haul flights or for businesspeople who frequently have telephone conversations with business associates in distant places. In the wake of the renaissance of the mechanical wristwatch, a wide variety of different world time systems have been developed.
A watch containing a world time complication.
A watch with a dial that can be changed to show the time in 24 different time zones represented by 24 major cities across the globe.
Provides testing equipment for timepieces. The company has headquarters in Buren an der Aare. it also owns a subsidairy in Hong Kong, with about 70 employees as of 2021.
A yacht timer is referred to by many names like a regatta timer, yachting chronograph, or sailing watch. A countdown timer designed for use in yacht racing, which involves reaching the starting line in a moving sailboat at speed just as the starting gun fires.
Yellow Gold is gold that is either pure or mixed with a zinc alloy or copper alloy to increase its strength while keeping its yellow color. The traditionally popular gold can be used in all gold, stainless steel, or other precious metal combinations. Yellow gold watches are some times found in 14k but most commonly found in 18k from most European manufacturers.
Round belt with the ecliptic in the middle that includes the twelve constellations through which the sun seems to pass in the course of a year.
Small additional dial or indicator that may be positioned, or placed off-center on the main dial, used for the display of various functions (e.g. second counters).