Applied chapter (Applique)

The hour numerals or decorations that are cut from sheets of metal then affixed to the dial.

Blanc roulant

A working movement without its escapement and ready for assembly, rating, adjusting and finishing.

Complication

Any function other than the indication of hours, minutes and seconds, regardless of whether the mechanism is hand-wound or self-winding, mechanical or electronic, and of movement height. The...

Disc

A flat, thin, round plate. The calendar disc rotates under the dial; its indications are shown through an aperture. Other discs display the day, month or moon phase.

Etablisseur

In Switzerland, a watchmaker who buys ébauches and parts to then assemble them.

Frame

J.C. Nicolet defines the frame as the chassis inside which all the parts of the watch movement are housed. A clock frame comprises two plates whereas a watch, and in particular wristwatch,...

Grain

A unit of weight for fine pearls: one grain equals a quarter of a carat or 0.05 grams. In stone-setting, the grain is a shaving of metal lifted from the mount and bent over the stone to...

Hand

A variously shaped indicator made from a thin piece of lightweight metal and which moves round a dial, with or without graduations. Most watches have three hands, one each for the hours, minutes...

Inclusion

An inclusion is a particle of foreign matter found within a gemstone. Inclusions can be another mineral, a liquid or a gas. Inclusions decrease the value of a diamond when visible with a 10X...

Jade

Jade is a gem group with jadeite and nephrite as the two varieties. Jadeite is the variety that ranges in colour from green to white to lilac to brown to almost black. Nephrite, the more ancient...

Light-Emitting Diode (LED)

A segmented luminous source used to display numerals on electronic digital watches. Operated by a push-button.

Microcrystallin

Microcrystalline is a type of mineral structure in which the crystals are so small that they can only be seen using a microscope. Agate, example is microcrystalline.

Natural pearl

A natural pearl is also called an oriental pearl. This pearl is formed by an oyster, freshwater mussel or other mollusc as a reaction to a tiny invading object that happened to be caught inside...

Oil sink

A cavity in bearings for a drop of oil.

Power reserve, Indicator

The time the watch will continue to function before the mainspring must be wound.

Quartz

Silicon dioxide. Also called rock crystal. Quartz has the specific property of vibrating at a very high frequency (32 MHz) placed under electric current. Under certain conditions, it...

Rough

The term used to describe a rock or a crystal in its natural state (before cutting or polishing).

Stippling (Spotting)

A decorative finish of overlapping circles in a close-set concentric pattern that gives a distinctive textured effect.

Tooth

A projection on the edge of a gear, escapement wheel, ratchet wheel, etc.

Universal Time (UT)

Since 1972, a continuation of Greenwich Mean Time (GMT) which is mean solar time at the Greenwich meridian. Universal Time (UT) is a measurement of time based on the Earth's...

Vane

Uses air friction to slow a moving part, for example the arm on a gravity escapement.

Water clock

Water clock: clepsydra with a system of gears.

Year

A four-digit indication of the current year that changes automatically at midnight on December 31st.

Zodiac

At the heart of countless legends and beliefs, since ancient times precious stones have had symbolic value. From the Jews to the Egyptians, each culture and religion has given a different meaning...