Glossary of Terms
In order for us to understand each other when talking about antique and period jewelry, we must have a common vocabulary. A great many jewelry terms are French. French jewelers were the leaders of the jewelry industry, and France is where the language of jewelry-making evolved. The terms used there were adopted by English and American jewelers and thus are part of our jewelry vocabulary today. Included in the list below are the most commonly used French jewelry terms with their approximate phonetic pronunciation (nasal and glottal sounds are difficult to transcribe) in brackets, and jewelry-related definitions. Words in SMALL CAPS are defined elsewhere in the Glossary; foreign words are italicized.
ADJUSTEDDerived from Latin ad justus, meaning just right Adjusted to compensate for temperature, positions and isochronism.
ALARM WATCHA watch that will give an audible sound at a pre-set time.
ALL or NOTHING PIECEA repeating Watch mechanism which ensures that ALL the hour & minutes are struck or sounded or nothing is heard.
ANALOGUEA term used to denote a watch dial with hands rather than digital display.
ANNEALINGHeating and cooling a metal slowly to relieve internal stress.
ANTI-MAGNETICNot affected by magnetic field.
ANTIQUARIANOf antiques or dealing in, also the study of old and out-of-date items.
ARBORThe mechanical axle of a moving part; on the balance it is called the staff, on the lever it is called the arbor.
ASSAYAnalyzing a metal for its gold or silver content.
AUTOMATONAutomatic working figures moving in conjunction with the movement mechanism. Striking Jacquemarts or jacks which are figures (may be humans provided with hammers) striking bells to supply the sound for the hour & quarter hours. The hammers take the place of the bells clapper, Automata plural of automaton.
AUXILIARY COMPENSATIONFor middle temperature errors found on marine chronometers.
AUXILIARY DIALAny extra dial for information.
AWIAmerican Watchmakers-Clockmakers Institute, 701 Enterprise Drive Harrison, OH 45030. Tel # (513) 367-9800
(BOX CASE) BREGUET KEYA ratcheting watch key permitting winding in only one direction.
BAGUETTEA French term for oblong shape. A watch having it's length at least 3 times it's width. A long narrow diamond.
BALANCE COCKThe bridge that holds the upper jewels and the balance and secured at one end only.
BALANCE SPRINGAlso called the hairspring; the spring governing the balance.
BALANCE STAFFThe shaft of the balance wheel.
BALANCE WHEELA device shaped like a wheel that does for a watch what a pendulum does for a clock.
BANKING PINSThe two pins that limit the angular motion of the pallet.
BAR MOVEMENTA type of movement employing about six bridges to hold the train. In use by 1840.
BARRELDrum-shaped container that houses the mainspring.
BEATRefers to the tick or sound of a watch; about 1/5 of a second. The sound is produced by the escape wheel striking the pallets.
BEETLE HANDHour hand resembling a stag beetle; usually associated with the poker-type minute hand in 17th and 18th century watches.
BELL METALFour parts copper and one part tin used for metal laps to get a high polish on steel.
BEZELThe rim that covers the dial (face) & retains the crystal. Above snap on bezel.
BI-METALLIC BALANCEA balance composed of brass and steel designed to compensate for temperature changes in the hairspring.
BLIND MANS WATCHA Braille watch; also known as a tact watch.
BLUINGBy heating polished steel to 540 degrees the color will change to blue.
BOMBEConvex on one side.
BOWThe ring that is looped at the pendant to which a chain or fob is attached
BOX CHRONOMETERA marine or other type chronometer in gimbals so the movement remains level at sea.
BOX JOINTED CASEA heavy hinged decorative case with a simulated joint at the top under the pendant.
BREGUET SPRINGA type of hairspring that improves time keeping also called over coil hairspring.
BRIDGEA metal bar which bear the pivot of wheels and is supported at both ends. (See cock.)
BUBBLE BACKA Rolex wristwatch that was waterproof (Oyster) and auto wind (Perpetual) Ca. 1930 to 1950's.
BUFFER SPRINGBuffer spring is a stop spring for oscillating weight.
BULL'S EYE CRYSTALUsed on old type watches; the center of the crystal was polished which achieved a bull's eye effect.
CABOCHONAn unfaceted cut stone of domed form or style. (On some crowns)
CALIBRESize of a watch movement also to describe the model, style or shape of a watch movement.
CAP JEWELAlso called the end stone, the flat jewel on which the staff rests.
CASE SCREWA screw with part of the head cut away.
CENTER WHEELThe second wheel; the arbor for the minute hand; this wheel makes one revolution per hour.
CHAINLooks like a miniature bicycle chain connecting the barrel and fusee.
CHAMFERSloping or beveled. Removing a sharp edge or edges of holes.
CHAMPLEVEAn area hollowed out and filled with enamel and then baked on.
CHAPTERThe hour, minute & seconds numbers on a dial. The chapter ring is the zone or circle that confines the numbers.
CHRONOGRAPHA movement that can be started and stopped to measure short time intervals and return to zero. A stopwatch does not keep the time of day.
CHRONOMETER ESCAPEMENTA detent escapement used in marine chronometers.
CLICKA pawl that ratchets and permits the winding wheel to move in one direction; a clicking sound can be heard as the watch is wound.
CLOCK WATCHA watch that strikes the hour but not on demand.
CLOISONNEEnamel set between strips of metal and baked onto the dial.
CLUB TOOTHSome escape wheels have a special design which increases the impulse plane; located at the tip of the tooth of the escape wheel
COARSE TRAIN16,000 beats per hour.
COCKThe metal bar that carries the bearing for the balance's upper pivot and is supported at one end.
COMPENSATION BALANCEA balance wheel designed to correct for temperature.
COMPLICATED WATCHA watch with complicated works; other than just telling time, it may have a perpetual calendar, moon phases, up and down dial, repeater, musical chimes or alarm.
CONTRATE WHEELA wheel with its teeth at a right angle to plane of the wheel.
CONVERTIBLEMovement made by Elgin & other companies; a means of converting from a hunting case to a open-face watch or vice versa.
CRAZEA minute crack in the glaze of enamel watch dials.
CROWNA winding button.
CROWN WHEELThe escape wheel of a verge escapement; looks like a crown. Also the lower illustration shows a crown wheel used in a stem winding pocket watch.
CURB PINSThe two pins that change the rate of a watch; the two pins, in effect, change the length of the hairspring.
CUVETTEThe inter dust cover of a pocket watch.
CYLINDER ESCAPEMENTA type of escapement used on some watches.
DAMASKEENINGThe art of producing a design, pattern, or wavy appearance on a metal. American idiom or terminology used in all American factory ads. The European terminology was Fausse Cotes or Geneva stripes.
DEMI-HUNTERA hunting case with the center designed to allow the position of the hands to be seen without opening the case.
DETENT ESCAPEMENTA detached escapement. The balance is impulsed in one direction; used on watches to provide greater accuracy. Detent a locking device.
DIALThe face of a watch. Some are made of enamel.
DISCHARGE PALLET JEWELThe right or 2nd jewel on lever. The 2nd of two pallet jewels with which a tooth of the escape wheel comes into engagement. Also called the Exit pallet.
DOUBLE ROLLERA watch with one impulse roller table and a safety roller, thus two rollers.
DRAWThe angular position of the pallet jewels in the pallet frame which causes those jewels to be drawn deeper into the escape wheel under pressure of the escape wheel's tooth on the locking surface.
DROPThe space between a tooth of the escape wheel and the pallet from which it has just escaped.
DUMB-REPEATERA repeating watch with hammers that strikes a block instead of bells or gongs.
DUPLEX ESCAPEMENTAn escape wheel with two sets of teeth, one for locking and, one for impulse.
EBAUCHEA movement not completely finished or in the rough; not de- tailed; a raw movement; a movement made up of two plates, train, barrel & did not include a dial, case, or escapement.
ECCENTRICNot exactly circular, Non-concentric. A cam with a lobe or egg shape.
ELECTRONIC WATCHNewer type watch using quartz and electronics to produce a high degree of accuracy.
ELINVARA hairspring composed of a special alloy of nickel, steel, chromium, manganese and tungsten that does not vary at different temperatures. Elinvar was derived from the words elasticity invariable.
END SHAKEThe up and down play of an arbor between the plates and bridge or between the jewels.
END STONEThe jewel or cap at the end of the staff.
ENGINE TURNINGEngraving a watchcase with a repetitive design by a machine.
EPHEMEROUS TIMEThe time calculated for the Earth to orbit around the sun.
ESCAPE WHEELThe last wheel in a going train; works with the fork or lever and escapes one pulse at a time.
ESCAPEMENTThe device in a watch by which the motion of the train is checked and the energy of the mainspring communicated to the balance. The escapement includes the escape wheel, lever, and balance complete with hairspring.
FARMER' S WATCHA large pocket watch with a verge escapement and a farm scene on the dial.
FECITA Latin word meaning "made by".
FIVE-MINUTE REPEATERA watch that denotes the time every five minutes, and on the hour and half hour, by operating a push piece.
FLINQUEEnameling over hand engraving.
FLY BACKThe hand returns back to zero on a timer.
FOBA decorative short strap or chain.
FOLIOTA straight-armed balance with weights on each end used for regulation; found on the earliest clocks and watches.
FORKThe part of the pallet lever that engages with the roller jewel.
FREE SPRUNGA balance spring free from the influence of a regulator.
FULL PLATEA plate (or disc) that covers the works and supports the wheels pivots. There is a top plate, a bottom plate, half, and 3/4 plate. The top plate has the balance resting on it.
FUSEEA spiral grooved, truncated cone used in some watches to equalize the power of the mainspring.
GOING BARRELThe barrel houses the mainspring; as the spring uncoils, the barrel turns, and the teeth on the outside of the barrel turn the train of gears as opposed to toothless fusee barrel.
GENEVA STOP WORKA system used to stop the works preventing the barrel from being over wound.
GILT (or GILD)To coat or plating with gold leaf or a gold color.
GOLD JEWEL SETTINGSIn high-grade watches the jewels were mounted in gold settings.
GOLD-FILLEDSandwich-type metal; a layer of gold, a layer of base metal in the middle, another layer of gold-then the layers of metals are soldered to each other to form a sandwich.
GRANDE SONNERIEA watch or clock that strikes the hour, 1/4 hours and minutes; if minute repeater, a Petite Sonnerie strikes hour only.
GREAT WHEELThe main wheel of a fusee type watch.
GUILLOCHEA decorative pattern of cross or interlaced lines. (Engraving style)
HACK-WATCHA watch with a balance that can be stopped to allow synchronization with another timepiece.
HAIRSPRINGThe spring that vibrates the balance. Also called balance spring.
HAIRSPRING STUDA hairspring stud is used to connect the hairspring to the balance cock.
HALLMARKThe silver or gold or platinum markings of many countries.
HEART CAM-PIECEA heart-shaped cam which causes the hand on a chronograph to fly back to zero.
HELICAL HAIRSPRINGA cylindrical spring used in chronometers
HOROLOGYThe study of time keeping.
HUNTER CASEA pocket watch case with a covered face that must be opened to see the watch dial.
IMPULSEThe force transmitted by the escape wheel to the pallet by gliding over the angular or impulse face of the pallet jewel.
IMPULSE PIN(Ruby pin)(roller jewel)-A pin or jewel on the balance roller table that keeps the balance going.
INCABLOCA patented shock-absorbing device that permits the end stone of the balance to give when the watch is subjected to an impact or jolt. 1st. used in 1933.
INDEPENDENT SECONDSA seconds hand driven independently by a separate train but controlled by the time train.
INDEXAnother term for the racquet shaped regulator, which lengthens or shortens the effective length of the hairspring.
ISOCHRONI5M"Isos" means equal; "chronos" means time- occurring at equal intervals of time. The balance and hairspring adjusted will allow the watch to run at the same rate regardless whether the watch fully wound or almost run down.
JEWELA bearing made of a ruby or other type jewel; the four types of jewels include; cap jewel, hole jewel, roller jewel or ruby pin, pallet jewel or stone.
KARRUSELAn invention of Bonniksen in 1894 which allows the entire escapement to revolve within the watch once in 52 1/2 minutes (in most karrusels), this unit is supported at one end only as opposed to the tourbillon which is supported at both ends and which most often revolves about once a minute.
KEY SETOlder watch that had to be set with a key.
L'Epine' CALIBREIntroduced by J.A. L'Epine about 1770. Swiss for open face.
LEAVESThe teeth of the pinion gears.
LEVER ESCAPEMENTInvented by Thomas Mudge in about 1759
LEVER SETTINGThe lever used to set some watches.
LOCKINGArresting the advance of the escape wheel during the balance's free excursion.
LUGSThe metal extensions of a wrist watch case which the bracelet or band are attached usually with a spring bar.
MAIN SPRINGA flat spring coiled or wound to supply power to the watch. The non-magnetic mainspring, introduced 1947.
MAIN WHEELThe first driving wheel, part of the barrel.
MALTESE CROSSThe part of the stop works preventing the barrel from being over wound.
MARINE CHRONOMETERAn accurate timepiece; may have a detent escapement and set in a box with gimbals which keep it in a right position.
MEAN TIMEAlso equal hours; average mean solar time; the time shown by watches.
MEANTIME SCREWSBalance screws used for timing, usually longer than other balance screws; when turned away from or toward the balance pin, they cause the balance vibrations to become faster or slower.
MICRO-SECONDA millionth of a second.
MICROMETRIC REGULATORA regulator used on railroad grade watches to adjust for gain or loss in a very precise way.
MINUTE REPEATERA watch that strikes or sounds the hours and minutes on demand.
MOVEMENTThe works of a mechanical watch without the case or dial. (quartz watches have modules)
MULTI-COLOR(Gold) Different colors of gold-red, green, white, blue, pink, yellow and purple.
MUSICAL WATCHA watch that plays a tune on demand or on the hour.
N. A. W. C. C.National Association of Watch and Clock Collectors 514 Poplar St. Columbia, Pa. 17512. TEL. 1-717-684-8261
NANOSECONDOne billionth of a second.
NURENBURG EGGNickname for a German watch that was oval-shaped.
OIGNONLarge older (1675) style watch in the shape of a onion or in the shape of a bulb.
OIL SINKA small well around a pivot which retains oil.
OVERBANKEDA lever escapement error; the roller jewel passes to the wrong side of the lever notch, causing one side of the pallet to rest against the banking pin and the roller jewel to rest against the other side, thus locking the escapement and stopping the motion of the balance.
OVERCOILThe raised up portion of the balance hairspring, not flat. Also called Breguet hairspring.
PAIR-CASE WATCHAn extra case around a watch-two cases, hence, a pair of cases. The outer case kept out the dust. The inner case could not be dustproof because it provided the access to the winding and setting keyholes in the watch case.
PALLADIUMOne of six platinum metals, used in watches in place of platinum, because it is harder, lighter and cheaper.
PALLETThe part of the lever that works with the escape wheel-jeweled pallet jewels, entry and exit pallets.
PARACHUTEAn early shock proofing system designed to fit as a spring on the end stone of balance.
PATINAOxidation of any surface & change due to age. A natural staining or discoloration due to aging.
PAVE'A number of jewels or stone set close together. Paved in diamonds.
PENDANTThe neck of the watch; attached to it is the bow (swing ring) and the crown.
PILLARSThe rods that hold the plates apart. In older watches they were fancy.
PINCHBECKA metal similar in appearance to gold. Named after the inventor. Alloy of 4 parts copper & 3 parts zinc.
PINIONThe larger gear is called a wheel. The small solid gear is a pinion. The pinion is made of steel in some watches.
PLATEA watch has a front and a back plate or top and bottom plate. The works are in between.
POISEA term meaning in balance to equalize the weight around the balance.
PONTILLAGE(bull's eye crystal)- The grinding of the center of a crystal to form a concave or so-called bull's eye crystal.
POSITIONAs adjusted to five positions; a watch may differ in its time keeping accuracy as it lays in different positions. Due to the lack of poise, changes in the center of gravity, a watch can be adjusted to six positions: dial up, dial down, stem up, stem down, stem left, and stem right. Note: Adj. to 5 positions is also 8 adjustments.
RACK & PINION LEVER ESCAPEMENTDeveloped by Abbe de Huteville in 1722 and by Peter Litherhead in 1791; does not use a roller table, but a pinion.
RECEIVING PALLETAlso called left or entrance jewel, the first of two pallet jewels with which a tooth of the escape wheel comes into engagement.
REPEATER WATCHA complicated watch that repeats the time on demand with a sounding device.
REPOUSSE'A watch with hammered, raised decoration on the case.
RIGHT ANGLE LEVER ESCAPEMENTalso called English escapement.
ROLLED GOLDThin layer of gold soldered to a base metal.
ROLLER JEWELThe jewel mounted or seated in the roller table, which receives the impulse from the pallet fork.
ROLLER TABLEThe part of the balance in which the roller jewel is seated.
ROTOROscillating weight for self-wind watches.
SAFETY PINIONA pinion in the center wheel designed to unscrew if the mainspring breaks; this protects the train from being stripped by the great force of the mainspring
SAFETY ROLLERThe smaller of the two rollers in a double roller escapement.
SAPPHIRE CRYSTALScratch resistant glass with a hardness of 9. Mineral glass has a hardness of 5.
SHAGREENThe skin of a horse, shark, ray fish & other animal usually dyed GREEN or a BLUE GREEN. Then used as ornamental covers for older watchcases.
SIDE-WINDERA mismatched case and movement; a term used for a hunting movement that has been placed in an open face case and winds at 3 o'clock position. Open face winds at 12 o'clock.
SIDEREAL DAYThe time of rotation of the Earth as measured from the stars. About 3 minutes 56 seconds shorter than the mean solar day.
SILVEROIDA type of case composed of alloys to simulate the appearance of silver.
SINGLE ROLLERThe safety roller and the roller jewel are one single table.
SIZESystem used to determine the size of the movement to the case.
SKELETON WATCHA watch made so the viewer can see the works. Plates are pierced and very decorative.
SKULL WATCHA antique pendant watch that is hinged at jaw to reveal watch.
SLOW TRAINA watch with four beats per second or 14,000 per hour.
SNAILA cam shaped much like a snail. The snail determines the # of blows to be struck by a repeater. (A count wheel)
SNAILINGOrnamentation of the surface of metals by means of a circle design; also called damaskeening.
SOLAR YEAR365 days, 5 hours, 48 minutes, 49.7 seconds.
SOUSCRIPTIONThe cheapest Breguet watch which he made with high quality made in batches or group lots in advance to lower the cost.(ebauches)
SPOTTINGDecoration used on a watch movement and barrel of movements.
SPRING BARThe metal keeper that attaches The band to The lugs of a wrist watch & is spring loaded.
SPRING RINGA circular tube housing a coiled type spring.
STACKFREEDCurved spring and cam to equalize the uneven force of the mainspring on 16th century German movements.
STAFFName for the axle of the balance.
SUN DIALA device using a gnomon or style that cast a shadow over a graduated dial as the sun progresses, indicating solar time.
SWIVELA hinged spring catch with a loop of metal that may be opened to insert a watch bow.
TOP PLATEThe metal plate that usually contains the name and serial #.
TORSIONA twisting force.
TOURBILLON(French for whirlwind) A watch that uses a escapement mounted in a carriage and pivoted at both ends and revolves 360 degrees at regular intervals of once a minute. The escape-pinion turns around the fixed fourth wheel. Design to eliminate position errors.
TRAINA series of gears that form the works of a watch. The train is used for other functions such as chiming. The time train carries the power to the escapement.
TRANSITION WATCHWatches sold with both key and stem-winding on same movement.
TRIPLE CASE WATCH18th and 19th century verge escapement, fusee watches made for the Turkish market. A fourth case sometimes added is called Quadruple case.
UP AND DOWN DIAL OR INDICATORA dial that shows how much of the mainspring is spent and how far up or down the mainspring is.
VERGE ESCAPEMENTEarly type of escapement with wheel that is shaped like a crown.
VERMEILGold plated over silver.
VIRGULE ESCAPEMENTEarly escapement introduced in the mid 1700s.
WATCH GLASS PROTECTORA snap on metal grill that covers the crystal.
WATCH PAPERA disc of paper with the name of the watchmaker or repairman printed on it; used as a form of advertising and found in some pair-cased watches.
WIND INDICATORA watch that indicates how much of the mainspring is spent. The illustration shows a modified Geneva stop works. (See up and down dial)
WOLF TEETHA winding wheel's teeth so named because of their shape.