WATCH TERMINOLOGY

Horology: The art and/or science of measuring time.

Haute Horlogerie: Translated to English, this French term means “high watchmaking,” and is used to distinguish watches or watchmakers that demonstrate extreme proficiency in watch design, technical innovation and finishing.

Manufacture d’Horlogerie: A French term, usually shortened to “manufacture,” that refers to a watch company that develops its own parts (including its movements) at its own facility (“in-house”), rather than assembling watches from parts made by third-party part suppliers.

Patina: A green or brown film on the surface of bronze or similar metals, produced by oxidation over a long period. In watches this mostly happens with the dial, however, bronze watches also develop a beautiful patina on the case over time.

Luminescence: Colloquially referred to as “lume,” luminescence is the glow given off by watch numerals, indices and hands that have been coated with a photoluminescent material. While early watches used radioactive radium to create lume, most modern watches use non-radioactive phosphorescent substances like strontium aluminate. Luminova - LumiNova®, also referred to as “lume”, is a photo-luminescent substance. When applied on watch dials and hands, it allows to tell time in the dark. Working as a kind of “light battery”, LumiNova® stores light, so it can then glows under weak luminosity conditions.

Super Luminova - is a brand name under which strontium aluminate–based non-radioactive and nontoxic photoluminescent or afterglow pigments for illuminating markings on watch dials, hands and bezels, etc. in the dark are marketed. This technology offers up to ten times higher brightness than previous zinc sulfide–based materials.

Tritium Tubes - Tritium radioluminescence is the use of gaseous tritium, a radioactive isotope of hydrogen, to create visible light. Tritium emits electrons through beta decay and, when they interact with a phosphor material, light is emitted through the process of phosphorescence. The overall process of using a radioactive material to excite a phosphor and ultimately generate light is called radioluminescence.

Water Resistance: Water Resistance is a really muddy subject in watch servicing. Watches are tested in extremely specific conditions and the water resistance marking are actually quite misleading, While 30m WR may give you the feeling that it is safe to get into any body of water that is a few feet deep, at WR 30m you’re actually only supposed to be able to wash your hands with the watch on - You aren’t meant to take it into the shower or submerge it at all.

10 mts = 1 ATM

WR 30M (3ATM) - Ideally just suitable to be used to wash hands and dishes.

WR 50M (5ATM) - Ideally just suitable to be used in a cold shower.

WR 100M (10ATM) - Ideally suitable to be used for swimming in swimming pools.

WR 200M (20ATM) -Ideally suitable for shallow open water swimming.

Diver’s 200M - Suitable for diving up to depths of under 200 metres.

There are a lot ratings that go beyond Diver’s 200M and these are ideally meant for professional deep diving at where the watch will have features to mechanically help divers to time their decompression stops.

Complication: An additional function of a watch that goes beyond telling the time, like a stopwatch (chronograph), calendar or a moonphase indicator. Complications require additional parts and make a watch more expensive and complex to build.

Timing Bezel: Rotating bezel used to count down to a specific time. Commonly used on diver’s watches.

Tachymeter: A scale inscribed around the rim of an analog watch. Used to compute speed based on travel time, or measure distance based on speed.

Counters: The hand on the chronograph function, started and stopped separately from the main time function.

Skeleton: Similar to an exhibition case back, a skeleton watch shows off the inner workings of the watch, but does so through a transparent or partially cut-out dial so that the movement can be viewed from the front of the watch.

Exhibition Case Back: Also called an “open” case back, this is a transparent cover on the backside of a watch case that shows off the inner workings of the movement.

Screw Crown: A winding crown which screws down onto the watch case. The purpose is to ensure water resistance.

Pusher: A button on a chronograph watch that starts, stops and/or resets the chronograph mechanism. The majority of chronographs have two pushers — one for starting and stopping the mechanism, and another for resetting. Diver’s Extension: Clasp with an extension, to enable easy enlargement of the bracelet to fit over a wet or dry suit.

Mainplate: The base on which all the parts of a mechanical watch movement are mounted.

Gear Train: A system of gears that transfer power from the mainspring to the escapement.

Jewels: Synthetic rubies (sometimes synthetic sapphires) used as bearings at the heaviest points of wear in a watch movement in order to reduce friction between moving parts and increase a movement’s lifespan. Jewels have a naturally slicker surface than metal — for example, the coefficient of friction between two pieces of steel is about 0.58, while the coefficient of sapphire on steel is about 0.15.

Desiccant crystal: A hygroscopic substance placed on the inside of the watch that sustains a state of dryness (desiccation) in its vicinity.

Counter: Also called a sub-dial. Chronographs have registers showing the second, minute, or hour of the chronograph function.

Small Seconds: A small sub-dial separate from the main hour and minute function that displays the seconds.

Retrograde: An indicator on a watch dial that forms a segment of a circle, rather than a full circle. When the indicator goes through a full cycle, it resets back to the zero position by moving backward. Often used to indicate hours, minutes or dates. Quartz: A quartz watch is a battery-powered watch. The battery sends an electric signal via a microchip circuit to a small quartz crystal that then vibrates at a precise rate. Those vibrations regulate a stepper motor that moves the watch hands. Quartz watches are considerably more accurate, more reliable and cheaper than their mechanical counterparts, though mechanical watch diehards don’t find them as appealing because of their simpler internal components.

Hand-wound: Referring to a mechanical watch that doesn’t automatically wind. Hand-wound watches are powered by manually turning the crown to wind up the mainspring.

Manual Winding: Describes a watch with a mechanical movement which needs to be wound regularly by the user using the crown. Energy is stored in the mainspring, which slowly releases this energy to power the time-piece.

Power Reserve: The length of time that a mechanical watch can run once it’s fully wound. Most entry-level watches have a power reserve of about 40 hours, though many higher-end watches can run for several days at a time. Sometimes watches will feature a power reserve gauge indicating how fully wound the watch is.

Automatic: A mechanical watch that is wound by the motion of the wearer’s wrist, rather than by twisting the crown. The motion of the wrist moves a counterweight (called a rotor) that then powers the mainspring, which turns the watch’s gears.

Winder: A case, box or vault that gently rotates an automatic watch to keep the mainspring fully wound when it isn’t being worn.

Figure 13. Rolex 2011 Patina on Vintage Dial Figure 14. Omega 2016 ‘Lume’ on Indices Figure 15. Rolex 2014 ‘Pepsi’ Timing Bezel

Figure 16. Audemars Piquet 2017 ‘Skeleton’ Watch Figure 17. Monochrome Watches 2009 Watch Jewels Figure 18. Sinn 2015 Decissant Crystal in Watch

Balance Wheel: A weighted wheel that oscillates at a constant rate (usually one oscillation per fraction of a second), moving the watch’s gears and allowing the hands to move forward

Balance Spring: A delicate spring (often made from metal but sometimes silicon) attached to the balance wheel that regulates the rate at which a balance wheel oscillates. The balance spring is also often referred to as a hairspring.

Mainspring: A torsion spring that becomes tightened when a watch is wound, thus storing the energy of a watch. The force of the spring unwinding powers the watch. The mainspring is housed inside a small drum called a “barrel.”

Barrel: 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 additional barrels.

Caliber: A synonym for movement, most often used when a manufacturer is denoting a specific model name for a movement.

Escapement: An internal component in a mechanical watch that transfers the power from a wound-up watch into the movement of the watch’s seconds hand by driving the balance wheel at a steady rate. Most modern watches use a “lever escapement,” comprised of an escape wheel and a lever with two pallets. The escape wheel is connected to the gear train (which receives energy from the mainspring) and the lever and pallets lock and unlock the escape wheel at a steady rate. This component is responsible for a watch’s ticking noise. Frequency: The speed at which a watch ticks (or beats), measured in either vibrations per hour or hertz. Most 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 considered to be high-beat watches. A watch’s frequency is controlled by the oscillations of its balance wheel.

Tourbillon: A type of escapement housed in a rotating cage that is meant to counter the negative effects gravity on a movement. While the movement was originally intended for pocket watches, they’ve moved to wristwatches as a way to showcase the height of a manufacturer’s watchmaking abilities, and as such, they command exorbitant prices

Carrousel: A carousel is a movement complication similar to a tourbillon.Like the tourbillon, a carousel continually rotates the balance wheel and escapement to counteract the influence of gravity. The tourbillon turns itself while the carousel requires a secondary gear to turn its mechanism The carousel is typically mounted on the fourth wheel, while the tourbillon is independent of this gear

Bridge: A plate or bar that is mounted to the mainplate, forming a frame that houses the inner workings of a mechanical watch.

Hacking Seconds: Also called “stop seconds,” this function will stop the seconds hand when the crown is pulled out. This makes it easier to synchronize a watch with another timepiece.

Repeater: A high-end complication that chimes to denote the time at the push of a button on the watch case. Oil-filled: Watch case that has had all the interior gasses replace with an oil. The purpose is to be able to withstand more exterior pressure.Side benefits include the constant lubrication and protection of the watch movement.

Magnetized Movement: Metal components inside a watch can often be magnetized when introduced to magnetic fields, thus causing a serious loss of accuracy. This happens mostly when the balance spring becomes magnetized and sticks to itself, causing the watch to run faster than usual. 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 highend watchmakers use soft-iron cages to protect the movement from magnetic fields, or use silicon balance wheels that do not become magnetized.

Chronometer: 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 former, watches are tested over the course several days in six different positions at three different temperatures, while remaining accurate to within -4/+6 seconds per day for mechanical watchesand ±0.07 per day for quartz watches.