Arbor

A synonym of axle (barrel arbor). A toothed wheel is fixed to the arbor, which is usually cylindrical, and both revolve.

Bow

Variously-shaped ring for suspending a pocket watch and fastening a chain.

Chronofiable

A joint certification project by a consortium of watch companies which accelerates the watch's ageing process by a factor of eight to simulate the effects of six months' wear in three weeks. The...

Dual time zone

Describes a watch that simultaneously gives the time in two time zones, usually local and the wearer's home.

Enamellist

A person who creates enamelwork.

Fancy diamonds

Rare diamonds which are naturally red, blue, green, or purple. Their price mainly depends on the saturation and quality of colour.

Gemstone

A gemstone (also called a precious stone) is a mineral that is rare, durable and beautiful. A few organic materials, like amber, coral and pearls are also considered gemstones.

Horn

That part of a watch case to which the strap is attached. Horns come in various shapes and are attached to the case middle.

Index (Regulator)

A device for adjusting a watch's rate by increasing or reducing the effective length of the balance spring. The index is a steel lever, the shorter end of which carries the curb pins which embrace...

Jewels

The international term for the jewels (rubies) in a watch movement that are used as bearings for pivots to reduce friction. The movement of a quality watch has between 15 and 21 jewels.

Kunzite

A transparent pink or light purple gemstone and is a variety of spodumene. The colour of some kunzite can be enhanced by irradiation. Kunzite has a hardness of 6-7 and a specific gravity of 3.1 -...

Leaf

The tooth on a pinion.

Marcasite

Marcasite is a misnomer for pyrite that has been cut in shiny metallic stones. It is sometimes found on watch bracelets and cases.

Nickel silver (German silver)

A silver-white alloy of copper, nickel and zinc developed in France circa 1820 by Maillot and Chorier from whom it takes its name.

Opaque

An optical characteristic of certain gemstones that do not transmit light either due to a very saturated colour or numerous inclusions.

Pallet

In a lever escapement, a small parallelepiped of ruby, sapphire or garnet, set in each of the lever's arms; one is the entrance pallet and one is the exit pallet.

Retrograde

An hour, minute, seconds or calendar hand which moves across a scale and, at the end of its cycle, returns immediately to zero to begin again.

Striking mechanism

An acoustic device that automatically or on demand indicates the hour, and possibly quarter-hour and minutes, or sounds at a pre-set time.There are different striking mechanisms: Passing...

Tourmaline

A dichroic gemstone that comes in all colours of the rainbow. Some crystals are bi or tri coloured. Tourmaline has the greatest colour range of any gemstone. Tourmaline has a hardness of 7-7.5 and...

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.

Watch

A portable timepiece that functions in all positions. A watch comprises three essential parts: The movement made up of the different mechanical components required to keep...

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...