Axle

A pivoted steel arbor on which the balance is mounted.

Bench

A general term for a solid workbench used by various professions. The watchmaker's bench includes drawers for the watchmaker to keep the different tools. These drawers form a cabinet which can be...

Cabinet

A small workshop in eighteenth and nineteenth-century Geneva, on the top floor of a house where there was the most natural light.

Diamond

Diamond is the hardest and most luminous precious stone. The price of a diamond is calculated according to the 4C criteria: Cut - Carat - Clarity - Color. The weight of a diamond is expressed in...

Fine stone

The name given to a non-precious stone. The term "semi-precious stone" is no longer...

Gear train

A system for transmitting power and motion through toothed wheels. In a watch, the train comprises a wheel whose teeth mesh with a pinion's leaves.

Heliotrope

Heliotrope is also known as bloodstone. It is a variety of chalcedony that is dark green with red specks. Heliotrope is used as watch dials.

Index for flat balance springs

An index that is often fitted with a screw or cam so that it can be adjusted by a very small amount for fine-tuning. The spring passes through the space between the curb pin and the boot.

Jasper

An opaque, ornamental stone found in many colours, including white, brown, yellow, red, and green. It is often striped, speckled, and multi-coloured and is used in watch making as a dial. Jasper...

Knot

A raised mineral inclusion in a diamond found at the surface.

Luminescent

Having the property to emit light rays. In watchmaking, Tritium is the name given to a radioluminescent substance containing tritium. It was used to coat numerals, markers and hands so they could...

Mohs scale

A relative scale of hardness established by the Austrian mineralogist Friedrich Moh that measures a substance's resistance to scratching. The scale ranges from 1 to 10; diamond being the hardness...

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...

Oscillating weight (Rotor)

In a self-winding movement, a heavy metal disc that turns freely in both directions to wind the mainspring.See rotor.

Perpétuelle

A term used by Breguet to refer to a self-winding watch.

Quartz oscillator

The regulating organ in a quartz clock or watch.

Resonance

This sophisticated technique, developed by Breguet and applied to wristwatches by François-Paul Journe, implies two fully independent movements: two mainsprings, two geartrains, two lever...

Split-seconds chronograph

The split-seconds chronograph is used to time different events that begin but do not end together. When set, the hand of the chronograph and the hand of the split seconds button when the first...

Transfer

Apply markings (numerals, signature, etc.) to the dial by means of a gelatine pad pressed onto an engraved and inked block.

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...

Vermeil

Silver covered with a thin layer of gold.

Water

The transparency and clarity of a precious stone; the orient and lustre of a pearl.

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...