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Cabochon
Also known as carbuncle, it is a stone with
a rounded,
domed surface and no facets.
Calcite
Calcite or Calcium Carbonate, CaCO3 is a very
common mineral that comes in a wide variety of forms, shapes and
colors. The trigonal crystals range from translucent to
transparent. Transparent calcite exhibits a double refraction
effects. It has a hardness of 3 (most forms), a specific
gravity of about 2.7, a refractive index of 1.49 and 1.66, and a
white streak.
Caliber – Cut
These are small stones cut into special shapes that are meant for use in commonly –
used designs. These stones usually have step-cut facets and are
generally rectangular shaped.
Carat
A standard measure of
weight used for gemstones. One carat weights 0.2 gram (1/5 of a gramor 0.0007 ounce).
Carbonaado
A rare type of opaque black diamond; they
are not used for jewels, but for items like drilling bits and
abrasive wheels. Unlike
other diamonds, carbonadoes are found in a crystallized form –
they are found in irregular or rounded fragments. Carbonadoes
have a hardness have a hardness of 10 and a specific gravity
(density) of 3.1-3.3. Diamonds have a very hard polycrystalline
carbon.
Carbuncle
A cabochon garnet.
Casting
The process of melting and molding metal. This process has
been used for thousands of years. Molds are made from many
materials, including plaster compounds. Some different methods of
casting include the lost wax process, centrifugal (or investment)
casting, and sand casting.
Cathedral Setting
A ring setting, it is a simple band
that arches ( like the arches of a cathedral) when seen from the
side.
Cat’s eye chrysoberyl
Cat’s eye or chatoyant chrysoberyl is a
yellow to green – yellow to gray-green stone with a bright, pupil
– like slit that seems to move slightly as the stone is moved. Cat’s eye chrysoberyl has a hardness of 8.5. This stone is
sometimes enhanced by irradiation (this process improves the
color and accentuates the stone’s asterism).
CFW
An abbreviation for Cultured
FreshWater pearls.
Chalcedony
It is a family of minerals
that are often milky to gray to bluish
in color. The family includes stones like agate, carnelian (waxy red),
chalcedony (blue), chrysoprose (green), onyx (black and white),
bloodstone, sard (brownish – red), jasper (home stone), seftonite,
and other. Chalcedony is porous and translucent and has harness of 6.5-7 and
specific gravity of 2.6.
Champleve
Means sunken enamel, it is a method of applying enamel to metal
in which the design is first outlined on the metal surface by
cutting lines into the surface. The engraved grooves are then
filled with enamel, then fired to a glassy sheen, and polished. Champleve is similar to cloisonne, but not as delicate.
Charm
Tiny, representational ornaments that are
worm on bracelets and necklaces.
Chasing
A style of metal decoration in
which the metal is manipulated using a hammer and punch,
that gives an effect similar to engraving or embossing.
Chaton
A stone with a reflective metal
foil backing.
Chaton setting
Also called coronet or
arcade setting, in this setting the stone is held in by many
metal claws around a metal ring.
Chatoyancy
A lustrous, cat’s eye effect
seen in some cabochon stones, like cat’s eye, tiger’s eye
(pictured above), and sometimes in other stones, like aquamarine.
In chatoyancy, light is reflected in thin bands within the stone.
Chenire
A fine, hollow tubing used
in the production of some jewelry findings (like clasps and
joints), and lately, in the actual production of jewelry. These tubes are lightweight and save in the use of gold. The
tubes are hard to bend when they are empty, so a metal rod is
inserted before bending, facilitating the bending.
Choker
A type of necklace that fits
tightly around the neck. Chokers are from 14” to 16”
in length.
Chrome Diopside
An emerald-green colored gemstone. It is a
chromium – rich variety of the common mineral Diopside (calcium
magnesium silicate).
Chromium
A hard, shiny, gray-white metal.
It can resist corrosion very well and is used in costume
jewelry as a coating over other metals.
Chrysoberyl
A hard stone comes in range of
colors from yellow, to brown, to green.
Chrysoprase
The most valued type of
the mineral chalcedony, it contains nickel that gives it an apple-green color. Chrysoprase
is porous and translucent. It is usually cut as a cabochon. It has a hardness of 7 and a
specific gravity of 2.6. Chrysoprase is also called “Australian
jade," sometimes, but it is not related to jade.
Cire Perdu
A process of casting metal in which the
original model is sculpted in wax. The wax is entombed in clay,
and then melted out, producing a hollow mold. The mold is then
filled with molten metal. The clay is broken off and the cast
metal remains.
Citrine
A
rare, yellow type of quartz, a semi-precious stone that ranges in
color from pale yellow to orange to golden brown. Citrine has a
hardness of 7 and a specific gravity of 2.65.
Clarity
The clearness of a gemstone, or
the lack of internal flaws. The clarity scale for diamonds runs
from FL (flawless, with neither Internal nor external flaws), to
13 (having many clearly visible imperfections using only the
naked eye). A ten-power loupe is used to examine a diamond for
clarity.
Clasp
A clasp is a fastener that can open and
close and attach two things together like the two ends
of a necklace, or a pin to a garment.
Claw
A metal prong used to hold a stone securely
in a setting.
Claw setting
A type of setting in which a series of
metal prongs or claws hold a stone securely in setting. This setting lets light in under the stone, so this type of
setting is usually used for transparent, faceted stones. The
modern-day claw setting became popular in the 1800’s.
Cleavage
The natural way in which a mineral
breaks, along certain planes based on its internal crystalline
structure.
Cloisonne
A method of applying enamel to
metal. In this method first the design is outlined on the metal surface
using a metal wire and then the space between the wires is filled
with enamel and finally it is fired to a glassy shine.
Closed setting
A setting in which the back of the stone is
not exposed.
Cloud
Usually composed of duster of
tiny inclusions it can be seen in the
gemstones with milky appearance.
Cluster setting
A setting in which small
stones or pearls are set around a larger stone and
form a cluster or group.
Collette setting
An olden method of setting gemstones. A
cullet is a thin, round band of metal that goes all around the
stone. One edge of the metal is crimped over the edges of the
stone and the other edge is soldered to the metal of the
jewelry, holding the stone in place. This closed setting
sometimes also had metal claws along the outside to hold the
stone even more securely.
Collaret
Also known as a bib necklace, it
is a short necklace with flowing ornaments at the front.
Composite suite
A piece of jewelry that
can be taken apart into two or more pieces and can also be worn
collected. For example, a necklace may be disassembled into two
bracelets.
Confetti Lucite
A transparent plastic with
glitter or other small pieces of matheral with in it, used to
make bangles, earrings, pins, necklaces and other jewelry pieces.
Copper
A soft metal used in making bronze, brass,
and gold alloys. It is also used to make jewelry items.
Coral
Coral is a sea animal that secretes a strong calcium structure that
is used in jewelry making. it is found in range of colors from pale pink
known as angelskin coral to orange to red to white to black. The
most valued colors are deep red (called noble coral) and pink. In
jewelry making, coral is either carved into beads, cameos, or
other forms, or is left in its natural branch –like form and just
polished.
Corundum
A very hard mineral with hardness
of 9 stands second in the hardness after diamond. Corundum is called ruby or sapphire,
depending on the color, (that is based on the presence of
the metallic oxides). In its rare pure form, corundum is
colorless and called white sapphire. Other impure forms are
opaque.
Crimp Bead
It is a soft, metal bead through
which string is threaded; the crimp
bead can be squeezed shut with a pliers to secure the end loops
of the threading material fasteners onto the clasps.
Crown
The upper part of a gemstone.
Crystal (Glass)
A high-quality glass that contain at least
10% lead oxide. Crystal is colored by adding various metallic oxide to the
melt.
Crystal (natural)
The natural crystal is a solid crystal,
that has atoms which form a very
regular structure. Some natural crystals are quartz, diamond, and
emerald.
Crystal Habit
The most common crystal habits:
Prismatic – elongated with paralles sides
like emerals, tourmaline
Tabular – short and flat (table-like), like
morganite
Ocatahedral – eight faces, like diamond
Dodecahedral – 12 faces, like garnet
Acicular – needle – shaped, like rultilated
quartz
Platy – occurring in very thin plates, like
hematite
Cubic Zirconium
Also known as cubic zirconia, it is an inexpensive, lab-produced gemstone that
looks like
a diamond.
Cufflinks
A men’s jewelry item that closes the
buttonholes of the cuff of a long sleeved shirt.
Culet
The bottom point of a gemstone or
a small facet that is ground at the base of a brilliant cut
gemstone. This culet helps to prevent splintering of the stone.
Culliana diamond
Also known as the star
of Africa, it is the largest diamond found till date, weighing 3,106
carats (roughly 1.3 pounds) in its rough form. It was mined at
the Premier Mine in South Africa in 1905 and was named for the
chairman of the company that owned the mine.
Cultured Pearl
Cultured pearls are produced by
surgically injecting the oysters with bits
of mussel shell. After 5-7 years, the oysters are retrieved and
the pearls are harvested. This method of “manufacturing” pearls
was invented in 1893 by Kokichi Mikimoto.
Cushion Cut
A pattern of stone cutting in which the stones are shaped like a cushion.
To form this shape the stones are cut in square shape and then
rounded on the edges.
Cut beads
Cutting faceted glass beads to make the bead reflect and refract more
light.
Cut stones
Styles of cutting a stone including the brilliant cut, old
European cut, emerald cut, radiant cut, rose cut, step cut, pendelique cut. Mixed cuts in which the style of the facets above
and below the girdle are different. Other, more unusual cuts, are
know as fantasy cuts (like the heart cut).
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