Cabochon
|
|
A stone that has a rounded, domed surface with no facets.
|
Calibre
|
|
Originally used to mean the size of a watch movement, this term now denotes a type of movement (men's calibre, automatic calibre, etc). When a calibre number is accompanied by the manufacturer's mark, it serves as an indication of origin.
|
Cameo
|
|
A relief carving (a carving that comes up above the surface) on a shell or stone.
|
Carat
|
|
1.
2. |
The unit of weight for a diamond or other gemstone and also for a pearl, equivalent to 200 mg.
Standard to define the fineness of gold and gold alloy, expressed as a number out of 24 parts, e.g. “14 carat” means 14/24ths gold in the alloy. 24 carat gold is pure gold. Most jewellery uses gold of 14 of 18 carats. For convenience, the fineness of gold may be expressed in thousandths rather than carats:
- 24 carats = 1,000 thousandths (1.000),
- 18 carats = 750 thousandths (0.750),
- 14 carats = 583 thousandths (0.583),
- 12 carats = 500 thousandths (0.500).
|
|
Carbonado
|
|
A rare type of opaque black diamond; they are not normally used for jewels, but for items like drilling bits and abrasive wheels.
|
Cat’s eye chrysoberyl
|
|
A yellow to green-yellow to grey-green stone with a bright, pupil-like slit that seems to move slightly as the stone is moved. Usually cut as cabochon.
|
Chalcedony
|
|
A family of minerals that is often milky to grey to bluish in colour.
|
Chatoyancy
|
|
The lustrous, cat’s eye effect seen in some cabochon stones, like tiger’s eye, and sometimes in other stones, like aquamarine.
|
Chime/Carillon
|
|
Watch mechanism to sound the time, usually by hammers striking gongs inside the case. A chime involving more than two gongs is called a carillon.
|
Chronograph
|
|
Watch or other apparatus with two independent time systems: one indicates the time of day, and the other measures brief intervals of time. Counters registering seconds, minutes and even hours can be started and stopped as desired.
|
Chronometer
|
|
Watch which has undergone a series of precision tests by an official institute in very unfavourable conditions.
|
Chrysoberyl
|
|
A hard stone that ranges in colour from yellow, to brown, to green.
|
Cluster setting
|
|
Setting in which small stones or pearls are set around a larger stone.
|
Coral
|
|
A hard, calcareous, organic substance that is the skeleton of certain polyps, small marine invertebrates that live in colonies. The variety used in jewellery is precious coral, which is compact and solid, without visible indentations. The colours shade from pinkish white to pale pink and ok-blood red. It is mainly used as beads or set en cabochon.
|
COSC
|
|
Contrôle Officiel Suisse des Chronomètres. Switzerland's official rating bureau for chronometers.
|
Citrine
|
|
Citrine (from the French for "lemon") is a rare, yellow type of quartz, a semi-precious stone that ranges in colour from pale yellow to orange to golden brown. The best quality citrine is found in Brazil.
|
Complications
|
|
Any horological function with the exception of the display of hours, minutes and seconds. Complicated watches are assigned to one of three categories: watches with one or several additional hands that have a timing function (watches with independent or jumping seconds, chronograph with minute registers or fly-back hands); watches with chimes (minute repeaters); and watches with astronomic indications (perpetual calendar, moon phases, equation of time). When a watch incorporates mechanisms of all three categories, it is referred to as a grand complication.
|
Cufflinks
|
|
Cufflinks are men's jewellery that closes the buttonholes of the cuff of a long-sleeved shirt. They were first worn in the 1800s.
|
Cultured pearl
|
|
Pearl whose formation is started by human intervention with the insertion a piece of mantle tissue into the oyster or mussel.
|
Cushion cuts
|
|
The most common shape for old or baroque brilliant-cuts. It has a rectangular or square cross-section, with rounded corners.
|
Chrome Diopside
|
|
Chrome diopside is an emerald-green coloured gemstone. It is a chromium-rich variety of the common mineral diopside.
BACK TO TOP
|
