“C” catch
The most common means of securing a brooch before 1900 or so when “safety catches” were invented. The pin connected to one side of the brooch is threaded through a layer of the garment and rests in a “C” shaped catch on the other side of the brooch. The “C” had no mechanism to hold the pin in place and so the pins were usually designed to be long enough to extend far enough beyond the end of the brooch to weave back into the garment for security.
C-OX
A green cubic zirconia (CZ) stone.
Cable Chain
A chain made of round linked rings of uniform size. This tends to be what most people think of when they think of the word “chain”. It is the same style of chain as the cable used to anchor large ships to a dock.
Cabochon
From the French “caboche”, meaning “knob/small dome”, a cabochon is a stone cut into the shape of a small dome in a round, oval, rectangle, triangle, or teardrop shape without any facets. This style is commonly used with opaque to translucent stones such as opal, moonstone, jade and turquoise. Some transparent stones such as emeralds, amethyst and garnet, are also sometimes fashioned as cabochons. An almandine (garnet) cabochon is called a “carbuncle”.
Cairngorm
Cairngorm is a yellow-brown type of smoky quartz that is often used in traditional Celtic jewelry. Cairngorm is not Scottish topaz. The supply of cairngorm is virtually exhausted, so heat-treated Brazilian amethyst is used as a substitute in Scottish jewelry.
Calcium
A silvery-white, moderately hard metallic element which is the fifth most abundant element comprising approximately 3% of the earth’s crust, and is a basic component of most animals and plants. It burns with a brilliant light and occurs naturally in limestone, gypsum, and fluorite.
Calcite
Calcite (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 effect (when you look through the crystal, singel items are doubled). Calcite 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.
Calibrated
A calibrated stone is one that has been cut exactly to a standard size, i.e. 5 mm, 10 mm x 14 mm. Jewelers often purchase calibrated cabochons or faceted stones when the design requires two or more stones of the same exact size or when a design will be duplicated many times as in manufactured jewelry.
Calibré Cut
Small stones cut in an oblong shape and set close together.
California ruby
A California ruby is actually a pyrope garnet (and not a ruby at all).
Calsilica
Rainbow calsilica is a newly-found, multi-colored, layered stone composed of calcium and silica. This stone has been recently used for Zuni fetish carvings and in some jewelry (beads and cabochon cut stones). Rainbow calsilica was only recently found in Mexico or Northern South America (it’s origin remains mysterious). Some people theorize that this stone formed as a result of the runoff of mining or oil-drilling chemicals, and has only formed in the last 30 to 50 years (but this is uncertain).
Cameo
A type of jewelry in which the stone around a design is cut away leaving the design in relief, typically against a contrasting background. Cameos are often made of shell and coral, although hard stone cameos such as agate, onyx, and sardonyx are more valuable. Cameos have been carved from the Hellenistic period, and ancient motifs such as the goddess Athena or a Baccante, (follower of Bacchus), were popular cameo subjects in Victorian times through the 1930’s. The opposite of a cameo is called “Intaglio”.
Cameo habille
A cameo habille (meaning “dressed cameo” in French) is a “jewel within a jewel,” a cameo in which the subject carved in the cameo (usually a woman) is wearing a miniature piece of jewelry (like a tiny diamond necklace with a stone embedded in the cameo).
Camphor glass
Camphor glass is cloudy white glass that is either blown or pressed. Camphor glass was very popular in the mid-nineteenth century and used for jewelry, candlesticks, vases, dishes, barometers, and other pieces. Camphor glass jewelry imitates rock crystal.
Canary diamonds
Canary diamonds are diamonds that have a deep yellow color. Diamonds are precious, lustrous gemstones made of highly-compressed carbon; they are one of the hardest materials known. Diamonds have a hardness of 10, a specific gravity of 3.5, and a refractive index of 2.417 – 2.419.
Cannetille
A wirework decoration which uses coiled and twisted gold wire to achieve a delicate scrolling effect.
Cape Amethyst
A form of Amethyst layered or striped with milky quartz.
Cape Ruby
A Cape ruby is actually a pyrope garnet (and not a ruby at all).
Carat
One of the 4 C’s of diamond grading. Abbreviated “ct.” and spelled with a “c” is a measure of weight used for gemstones, (as opposed to karat with a “K”, which is a measure of the purity of a gold alloy). One carat is equal to 1/5 of a gram (200 milligrams). Stones are measured to the nearest hundredth of a carat. A hundredth of a carat is also called a point. Thus a .10 carat stone can be called either 10 points, or 1/10 of a carat. Small stones like .05, and .10ct are most often referred to by point designations. A one carat round diamond of average proportions is approximately 6.5mm in diameter. Note that this relationship of weight and size is different for each family of stones. For example ruby and sapphire are both heavier than diamond (technically, they have a higher specific gravity, so a 1 carat ruby or sapphire is smaller in size than a one carat diamond.)
Carbon
A non-metallic element that occurs in all organic compounds and many inorganic compounds. Carbon is combustible and has the interesting ability to bond with itself, as well as with many other elements.
Carbonado
A carbonardo is a rare type of opaque black diamond; they are not used for jewels, but for items like drilling bits and abrasive wheels. They were once thought to have been formed as a result of a comet impact 2 billion years ago, but this is no longer thought to be true. The largest diamond ever found was a carbonardo that weighed over half a kilogram. Carbonadoes are found in Bahia, Brazil, South America. Unlike other diamonds, carbonadoes are not found in a crystallized form – they are found in irregular or rounded fragments. Carbonadoes have a hardness of 10 and a specific gravity (density) of 3.1-3.3. Diamonds have a very hard polycrystalline carbon structure.
Carbon Spots
Diamonds are carbon that has been compressed over time. Carbon spots are a kind of flaw, or “inclusion”, found in diamonds showing as black spots inside the clear diamond.
Carbonate
A substance treated with carbon dioxide, such as limestone.
Carbuncle
An almandine (garnet) cabochon.
Carnelian
A translucent red or orange variety of chalcedony, sometimes banded red and orange like an agate. Once believed to benefit the wearer’s health and love life. Most carnelian comes from Brazil, India, Siberia, and Germany.
Casting
A means of reproducing an object by making a mold of it and pouring metal, plaster, or some other material that sets over time into the mold. See Centrifugal casting, Electrotype, Lost wax process, and sand casting.
Catalin
See Bakelite.
Cathedral Setting
A cathedral ring setting is a simple band that arches when seen from the side (like the arches of a cathedral).
Cat’s eye
Cat’s eye (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. Most Cat’s eye is cut as cabochons to maximize the distinctive pupil-like effect. Most cat’s eye chrysoberyl is found in Brazil. 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).
CE
Common Era, or in the Christian calendar, AD, anno domini, meaning “in the year of our Lord”.
Cell Enameling
See Cloisonné.
Celluloid
A plastic derived from cellulose, a natural plant fiber, first synthesized around 1870 as a synthetic ivory. It can be cut, rolled, folded, perforated, ironed, turned, or embossed when heated, but cannot be injected. Celluloid is flammable and deteriorates easily if exposed to moisture. jewelry made of celluloid was often set with rhinestones. Hair combs and other dresser articles are still often made of celluloid today. Also called French ivory, Ivoride, Ivorine, Ivorite, and Pyralin
Celtic jewelry
Celtic jewelry was made by the Celts in Ireland, Wales, Scotland, and Brittany. The Celts used bronze, silver and gold in their jewelry and stones like cairngorm and amethyst. Circular brooches with a long, hinged pin, called penannular brooches, date from ancient times. The earliest-known piece of Celtic jewelry is the Hunterston brooch from A.D. 700
Celtic Revival
Jewelry made during the mid-nineteenth century reflective of the styles of jewelry used in early Ireland based on archaeological artifacts.
Center Stone
Usually a diamond, (or other gemstone), that is the prominent center piece in a ring setting.
Centrifugal Casting
A method of casting jewelry in which molds are attached to the outside edge of hollow tube. Metal is poured into the tube and as the tube is spun at high speed centrifugal force pulls the molten metal into the molds.
Certification
A grading report given to a precious stone by a reputable and recognized laboratory that defines the physical characteristics and quality rating of a gem. See Assay and IGI
CFW
CFW is an abbreviation for cultured freshwater pearls.
Chain
A strand of linked loops, rings, or beads used for bracelets or necklaces. Popular types of chain include: Book chain, Box, Butterfly, Byzantine, Cable, Cuban, Curb, Figaro, Figogucci, Foxtail, Herringbone, Marina, Mariner, Mesh, Omega, Panther link, Rolo, Rope, San Marco, Serpentine, Singapore, and Snake. (See individual listings.)
Chalcedony
A family of colored quartz stones including agate, onyx, carnelian, cat’s eye, and jasper that commonly have a milky or waxlike luster. When chalcedony is variegated with with spots or figures, or arranged in differently colored layers, it is called agate; and if by reason of the thickness, color, and arrangement of the layers it is suitable for being carved into cameos, it is called onyx.
Champagne Diamond
A champagne diamond is a pinkish brown diamond (having a color of C2-C3). Most champagne diamonds are mined in Western Australia (in the Argyle Mine). The color is produced by a their low nitrogen content
Champlevé
A type of enameling in which powdered glass is placed in areas of a piece of jewelry that have been carved away specifically for this purpose before firing. The glass powder melts filling the carved areas with solid glass.
“C” catch
The most common means of securing a brooch before 1900 or so when “safety catches” were invented. The pin connected to one side of the brooch is threaded through a layer of the garment and rests in a “C” shaped catch on the other side of the brooch. The “C” had no mechanism to hold the pin in place and so the pins were usually designed to be long enough to extend far enough beyond the end of the brooch to weave back into the garment for security.
C-OX
A green cubic zirconia (CZ) stone.
Cable Chain
A chain made of round linked rings of uniform size. This tends to be what most people think of when they think of the word “chain”. It is the same style of chain as the cable used to anchor large ships to a dock.
Cabochon
From the French “caboche”, meaning “knob/small dome”, a cabochon is a stone cut into the shape of a small dome in a round, oval, rectangle, triangle, or teardrop shape without any facets. This style is commonly used with opaque to translucent stones such as opal, moonstone, jade and turquoise. Some transparent stones such as emeralds, amethyst and garnet, are also sometimes fashioned as cabochons. An almandine (garnet) cabochon is called a “carbuncle”.
Cairngorm
Cairngorm is a yellow-brown type of smoky quartz that is often used in traditional Celtic jewelry. Cairngorm is not Scottish topaz. The supply of cairngorm is virtually exhausted, so heat-treated Brazilian amethyst is used as a substitute in Scottish jewelry.
Calcium
A silvery-white, moderately hard metallic element which is the fifth most abundant element comprising approximately 3% of the earth’s crust, and is a basic component of most animals and plants. It burns with a brilliant light and occurs naturally in limestone, gypsum, and fluorite.
Calcite
Calcite (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 effect (when you look through the crystal, singel items are doubled). Calcite 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.
Calibrated
A calibrated stone is one that has been cut exactly to a standard size, i.e. 5 mm, 10 mm x 14 mm. Jewelers often purchase calibrated cabochons or faceted stones when the design requires two or more stones of the same exact size or when a design will be duplicated many times as in manufactured jewelry.
Calibré Cut
Small stones cut in an oblong shape and set close together.
California ruby
A California ruby is actually a pyrope garnet (and not a ruby at all).
Calsilica
Rainbow calsilica is a newly-found, multi-colored, layered stone composed of calcium and silica. This stone has been recently used for Zuni fetish carvings and in some jewelry (beads and cabochon cut stones). Rainbow calsilica was only recently found in Mexico or Northern South America (it’s origin remains mysterious). Some people theorize that this stone formed as a result of the runoff of mining or oil-drilling chemicals, and has only formed in the last 30 to 50 years (but this is uncertain).
Cameo
A type of jewelry in which the stone around a design is cut away leaving the design in relief, typically against a contrasting background. Cameos are often made of shell and coral, although hard stone cameos such as agate, onyx, and sardonyx are more valuable. Cameos have been carved from the Hellenistic period, and ancient motifs such as the goddess Athena or a Baccante, (follower of Bacchus), were popular cameo subjects in Victorian times through the 1930’s. The opposite of a cameo is called “Intaglio”.
Cameo habille
A cameo habille (meaning “dressed cameo” in French) is a “jewel within a jewel,” a cameo in which the subject carved in the cameo (usually a woman) is wearing a miniature piece of jewelry (like a tiny diamond necklace with a stone embedded in the cameo).
Camphor glass
Camphor glass is cloudy white glass that is either blown or pressed. Camphor glass was very popular in the mid-nineteenth century and used for jewelry, candlesticks, vases, dishes, barometers, and other pieces. Camphor glass jewelry imitates rock crystal.
Canary diamonds
Canary diamonds are diamonds that have a deep yellow color. Diamonds are precious, lustrous gemstones made of highly-compressed carbon; they are one of the hardest materials known. Diamonds have a hardness of 10, a specific gravity of 3.5, and a refractive index of 2.417 – 2.419.
Cannetille
A wirework decoration which uses coiled and twisted gold wire to achieve a delicate scrolling effect.
Cape Amethyst
A form of Amethyst layered or striped with milky quartz.
Cape Ruby
A Cape ruby is actually a pyrope garnet (and not a ruby at all).
Carat
One of the 4 C’s of diamond grading. Abbreviated “ct.” and spelled with a “c” is a measure of weight used for gemstones, (as opposed to karat with a “K”, which is a measure of the purity of a gold alloy). One carat is equal to 1/5 of a gram (200 milligrams). Stones are measured to the nearest hundredth of a carat. A hundredth of a carat is also called a point. Thus a .10 carat stone can be called either 10 points, or 1/10 of a carat. Small stones like .05, and .10ct are most often referred to by point designations. A one carat round diamond of average proportions is approximately 6.5mm in diameter. Note that this relationship of weight and size is different for each family of stones. For example ruby and sapphire are both heavier than diamond (technically, they have a higher specific gravity, so a 1 carat ruby or sapphire is smaller in size than a one carat diamond.)
Carbon
A non-metallic element that occurs in all organic compounds and many inorganic compounds. Carbon is combustible and has the interesting ability to bond with itself, as well as with many other elements.
Carbonado
A carbonardo is a rare type of opaque black diamond; they are not used for jewels, but for items like drilling bits and abrasive wheels. They were once thought to have been formed as a result of a comet impact 2 billion years ago, but this is no longer thought to be true. The largest diamond ever found was a carbonardo that weighed over half a kilogram. Carbonadoes are found in Bahia, Brazil, South America. Unlike other diamonds, carbonadoes are not found in a crystallized form – they are found in irregular or rounded fragments. Carbonadoes have a hardness of 10 and a specific gravity (density) of 3.1-3.3. Diamonds have a very hard polycrystalline carbon structure.
Carbon Spots
Diamonds are carbon that has been compressed over time. Carbon spots are a kind of flaw, or “inclusion”, found in diamonds showing as black spots inside the clear diamond.
Carbonate
A substance treated with carbon dioxide, such as limestone.
Carbuncle
An almandine (garnet) cabochon.
Carnelian
A translucent red or orange variety of chalcedony, sometimes banded red and orange like an agate. Once believed to benefit the wearer’s health and love life. Most carnelian comes from Brazil, India, Siberia, and Germany.
Casting
A means of reproducing an object by making a mold of it and pouring metal, plaster, or some other material that sets over time into the mold. See Centrifugal casting, Electrotype, Lost wax process, and sand casting.
Catalin
See Bakelite.
Cathedral Setting
A cathedral ring setting is a simple band that arches when seen from the side (like the arches of a cathedral).
Cat’s eye
Cat’s eye (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. Most Cat’s eye is cut as cabochons to maximize the distinctive pupil-like effect. Most cat’s eye chrysoberyl is found in Brazil. 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).
CE
Common Era, or in the Christian calendar, AD, anno domini, meaning “in the year of our Lord”.
Celebrity
Celebrity is a mark of generally low- to medium-quality costume jewelry made by a New York company. The trademark “Celebrity” is owned by the Celebrity Jewelry Company of Philadelphia, Pennnsylvania, which makes jewelry of gold and silver, with precious stones.
Cell Enameling
See Cloisonné.
Cellini, Benvenuto
Benvenuto Cellini (1500-1571) was the pre-eminent Italian jeweler during the renaissance. Cellini’s intricate works utilized beautifully-cast metals, enamel, table-cut gems, and pearls
Celluloid
A plastic derived from cellulose, a natural plant fiber, first synthesized around 1870 as a synthetic ivory. It can be cut, rolled, folded, perforated, ironed, turned, or embossed when heated, but cannot be injected. Celluloid is flammable and deteriorates easily if exposed to moisture. jewelry made of celluloid was often set with rhinestones. Hair combs and other dresser articles are still often made of celluloid today. Also called French ivory, Ivoride, Ivorine, Ivorite, and Pyralin
Celtic jewelry
Celtic jewelry was made by the Celts in Ireland, Wales, Scotland, and Brittany. The Celts used bronze, silver and gold in their jewelry and stones like cairngorm and amethyst. Circular brooches with a long, hinged pin, called penannular brooches, date from ancient times. The earliest-known piece of Celtic jewelry is the Hunterston brooch from A.D. 700
Celtic Revival
Jewelry made during the mid-nineteenth century reflective of the styles of jewelry used in early Ireland based on archaeological artifacts.
Center Stone
Usually a diamond, (or other gemstone), that is the prominent center piece in a ring setting.
Centrifugal Casting
A method of casting jewelry in which molds are attached to the outside edge of hollow tube. Metal is poured into the tube and as the tube is spun at high speed centrifugal force pulls the molten metal into the molds.
Certification
A grading report given to a precious stone by a reputable and recognized laboratory that defines the physical characteristics and quality rating of a gem. See Assay and IGI
CFW
CFW is an abbreviation for cultured freshwater pearls.
Chain
A strand of linked loops, rings, or beads used for bracelets or necklaces. Popular types of chain include: Book chain, Box, Butterfly, Byzantine, Cable, Cuban, Curb, Figaro, Figogucci, Foxtail, Herringbone, Marina, Mariner, Mesh, Omega, Panther link, Rolo, Rope, San Marco, Serpentine, Singapore, and Snake. (See individual listings.)
Chalcedony
A family of colored quartz stones including agate, onyx, carnelian, cat’s eye, and jasper that commonly have a milky or waxlike luster. When chalcedony is variegated with with spots or figures, or arranged in differently colored layers, it is called agate; and if by reason of the thickness, color, and arrangement of the layers it is suitable for being carved into cameos, it is called onyx.
Champagne Diamond
A champagne diamond is a pinkish brown diamond (having a color of C2-C3). Most champagne diamonds are mined in Western Australia (in the Argyle Mine). The color is produced by a their low nitrogen content
Champlevé
A type of enameling in which powdered glass is placed in areas of a piece of jewelry that have been carved away specifically for this purpose before firing. The glass powder melts filling the carved areas with solid glass.
Chandelier Earring
An earring with a drop suspended like a chandelier. Also called a “Drop Earring” or “Dangle Earring”.
Channel Inlay
A design similar to enameling in which stones, rather than melted plastic or glass, are cut to shape and set into the recesses of a piece of jewelry. Commonly seen with jewelry using mother of pearl and turquoise.
Channel Set
A style of setting in which a number of uniformly sized small stones, usually of the round cut, princess cut or baguette shapes, are set side by side in a grooved channel. Unlike most setting methods the stones are not secured individually with prongs and there is no metal visible between the stones.
Chaplet
A garland, wreath, or ornamented band worn around the head. Chaplets are made of metal with repoussé decoration or embellished with gemstones and pearls.
Charel
Charel is a mark of relatively rare, medium-quality costume jewelry made by the Charel Jewelry Company, Inc. of Brooklyn, New York. Many Charel pieces have pastel-colored plastic stones on plated metal.
Charm
A pendant or trinket worn on a bracelet, earring or necklace.
Charm Bracelet
A chain link bracelet with charms attached to it. (It’s not a charm bracelet until it has charms attached.)
Charm Ring
A ring with a charm attached to the ring band.
Charoite
Charoite is a fairly recent discovery found in Russia in 1978 in the Murun mountains in Yakutia, near the Charo River. This is the only known location for this rare mineral.
It ranges in color from a light lilac to a deep purple and can be mottled with gray, white and black inclusions. The chatoyant variety in a bright deep purple, is usually considered more valuable than the non-chatoyant variety although both are used in jewelry and compliment a number of other stones.
Chasing
A method of decorating the front, (or outside), of metal objects by making indentations using shaped punches and a chasing hammer. The opposite of chasing is repoussé.
Chatelaine
French for “Lady of the House”, a chatelaine is an ornamental chain or pin worn at a woman’s waist from which dangle keys, trinkets, scissors, needle cases, pencils, purse, etc. Chatelaines may be utilitarian or beautifully decorated and made from precious materials like silver.
Chatham synthetic rubies
Chatham synthetic rubies (laboratory-created rubies) were introduced by Carroll Chatham in 1959.
Chaton
A cone shaped rhinestone or crystal.
Chaton setting
A châton setting (also called coronet or arcade setting) is one in which the stone is held in by many metal claws around a metal ring.
Chatoyancy
Chatoyancy is the 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. Chatoyant stones are cut in cabochon to maximize the lustrous effect.
Chatoyant
A stone having a changeable luster due to the way it reflects light, such as the cat’s-eye or tiger’s eye gemstones. From the French “chatoyer”, meaning to shimmer like cats’ eyes, from the French “chat” meaning “cat”.
Chenier
Chenier is fine, hollow tubing that is used in the production of some jewelry findings (like clasps and joints), and lately, in the actual production of jewelry. The hollow 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.
Chevron setting
A chevron is a design found in heraldry resembling a shallow inverted “V”. In jewelry design, a “chevron setting” is reflective of the heraldic chevron in that it is made up of lines in a shallow inverted “V” pattern.
Chinese opal
Chinese opal is a misnomer for pearl opal (a type of organic opal), moonstone, or white chalcedony
Chloride
Any compound containing a chlorine atom.
Chlorine
An abundant element which, when isolated, appears as a poisonous, greenish-yellow gas with a disagreeable odor. It occurs naturally only as a salt, as in sea-water. Chlorine is used widely to purify water, as a disinfectant and bleaching agent, and in the manufacture of many important compounds including chloroform and carbon tetrachloride.
Choker
A close fitting necklace worn tight around the neck like a collar.
Chrome
A hard, brittle, grayish white metal, fusible with difficulty and resistant to corrosion. Its chief commercial importance is for its compounds, as potassium chromate, lead chromate, etc., which are brilliantly colored and are used dyeing and calico printing. The common modern usage is for very shiny metal objects like chrome bumpers, etc.
Chrome diopside
Chrome diopside is an emerald-green colored gemstone. It is a chromium-rich variety of the common mineral diopside (Calcium magnesium silicate). Chrome diopside has a hardness of 5 to 6 and a specific gravity of 3.3 to 3.6.
Chromium
A lustrous, hard brittle, steel-blue metallic element, resistant to corrosion and tarnishing. It is used in the hardening of steel alloys and the production of stainless steels, in corrosion-resistant decorative platings, and as a pigment in glass.
Chronograph
A chronograph is a stopwatch mechanism on a watch; it can be started, stopped and reset independently from the watch.
Chrysoberyl
A rare, hard, yellow-green mineral consisting of alumina and glucina, (beryllium aluminate), in crystal form. It is popular as a gemstone for its chatoyant qualities.
Chrysocolla
Chrysocolla (meaning “golden lime” in Greek) is an opaque blue to blue-green mineral sometimes used in jewelry. It is usually cut as a cabochon. Chrysocolla (hydrated copper silicate) is found embedded in rock crystal in copper mines in the USA, Russia, Chile, and the Congo. Although Chrysocolla has been used in ornaments since the time of the ancient Greeks, it was only described mineralogically in 1968. Its hardness varies from 2 to 4.
Chrysolite
A mineral composed of silica, magnesia, and iron sometimes used as a gem. Chrysolite ranges in color from a light pea green to a deep olive green and an oily shine. It is common in certain volcanic rocks and meteorites. Mystics have claimed that this lustrous green stone drives away evil and has special healing properties. The name chrysolite has been used in the past for yellow varieties of tourmaline and topaz.
Chrysoprase
Chrysoprase is the most valued variety of the mineral chalcedony (microcrystalline quartz) that contains nickel, giving it an apple-green color. Chrysoprase is porous and translucent. It is usually cut as a cabichon, and has been used since ancient times. Chrysoprase has a hardness of 7 and a specific gravity of 2.6. Chrysoprase is mined in Australia, Russia (the Ural Mtns.), Brazil, and the western USA. Chrysoprase is sometimes called “Australian jade,” but it is not related to jade. Hard-to-detect imitation chrysoprase is made by staining agate with chromium salts.
Cigar band
A very wide band-style ring.
Cinnabar
Cinnabar is the mineral Mercury Sulfide. Its color ranges from cinnamon to scarlet to brick red and it can be translucent to transparent. It is often carved. Cinnabar has a hardness of 2 – 2.5 (very soft) and a specific gravity of 8.1 (quite heavy).
Cinnamon stone
A brown or yellowish-brown variety of garnet more properly called “essonite”.
Cire perdu
Cire perdu (French for “lost wax”) is a process of casting metal in which the original model is sculpted in wax. The wax is entombed in clay, and the wax is 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
Named after the French word for lemon, “citron”. Citrine is often incorrectly called quartz topaz or citrine topaz. A variety of quartz, citrine is found in light yellow, amber-brown, and a brilliant orange that may be confused with fine imperial topaz. Most citrine comes from South America. In ancient times, citrine was revered as a gift of the sun and believed to be a powerful antidote to a viper’s venom. Citrine is the birthstone for November.
Claddagh Ring
First crafted by Master Goldsmith Richard Joyce in 1689, it is named after Claddagh, the fishing village he lived in at the time, which overlooks Galway Bay. The ring belongs to a class of rings called “Fede” or “Faith rings”, which date from Roman times and were popular in the Middle Ages throughout Europe. Whereas “Fede” rings have only two clasped hands, symbolizing faith, trust, or “plighted troth”, Claddagh rings have two hands clasping a heart, symbolizing love, surmounted by a crown, symbolizing loyalty. The ring worn on the right hand with the heart turned outward indicates that your heart is yet unoccupied. Worn on the right hand with the heart turned inward indicates that love is being considered. Worn on the left hand the with the heart turned inward shows everyone that your heart is truly spoken for.
Clarity
One of the 4 C’s of diamond grading. Gemstones with the highest clarity contain few or no inclusions (imperfections) in the stone’s crystalline structure. Clarity is graded with a 10x magnifier. The clarity rating of a diamond ranges from FL (flawless) to I (inclusions visible to the naked eye).
Clasp
A device used to connect two ends of a necklace, bracelet or watch strap. Popular types of clasps include: Barrel, box, Lobster claw, and Spring ring clasps. (See individual listings).
Class Ring
A ring that commemorates graduating from high school. It is usually engraved with the name of the school, the year of graduation, and a gem featuring one of the school’s colors.
Claw
A claw is a metal prong that holds a stone securely in a setting.
Claw Setting
A way of securing a stone in its mount using small prongs that surround it.
Cleaning Jewelry
The safest and easiest way to clean most jewelry is with a detergent bath. Swish together warm water and any mild liquid detergent. Clean the jewelry with a soft brush while it’s in the suds, then rinse it under warm running water. Pat it dry with a soft, lint-free cloth. Avoid using brushes, which can scratch gold. Never boil gold, and avoid using ammonia, toothpaste, a powder cleanser or scouring pads. Keep gold away from chlorine, lotions, cosmetics and perm solutions, since these products may discolor or dissolve gold alloys. gemstones rarely need cleaning unless they become dirty from hand lotion, hairspray or other products. They can be cleaned using a soft cloth with mild soap and water, but rinse well. If you are using a silver or gold jewelry dip solution, most are safe for gemstones, but read the label to make sure. Do not boil gemstones. Do not wear pearls while applying cosmetics, hair sprays or perfume. It’s best not to wear pearl strands while bathing, because water can weaken the string. Wipe pearl strands with a damp cloth after each use. Do not clean cultured pearls with chemicals, abrasives or jewelry cleaner.
Clear Quartz
A colorless transparent mineral consisting of silicon dioxide in crystal form. See Quartz.
Cleavage
Cleavage is the tendency which a stone has to fracture along its crystal structure.
Clip-on
A piece of jewelry designed to be attached by means of a clip, such as a clip-back earring.
Clip-back Earring
A hinged ring with a pad, called a “comfort back”, at one end to secure the earring to the earlobe without requiring that the ear be pierced.
Cloisonné
Occasionally called “cell enameling”, it is a type of enameling in which compartments made of thin strips of metal soldered onto a metal plate are filled with powdered glass prior to firing. The glass powder melts filling the compartments with solid glass.
Closed Setting
A closed setting is one in which the back of the stone is not exposed (the metal is not cut away behind the stone).
Cloud
A form of inclusion, “clouds” are white milky areas that can found in the diamond.
Cluster
Several stones grouped together in a jewelry setting.
Cluster Brooch
A brooch developed in the 14th century in which a large central gemstone is surrounded by a cluster of smaller gemstones and pearls.
Cluster Earring
A decorative earring made up of a cluster of glass and/or metal beads and stones
Cluster Ring
A ring featuring a central gemstone surrounded by a number of smaller stones.
Cluster setting
A cluster setting is one in which small stones or pearls are set around a larger stone.
Clutch
A device that is slid along a post to secure a piece of jewelry, such as the earring back of a stud for pierced ears.
Cocktail Ring
A large oversized ring set with precious or semiprecious stones popular during the 1940s and 1950s.
Cognac Diamond
A cognac diamond is a cognac-brown diamond (having a color of C7). Most cognac diamonds are mined in Western Australia (in the Argyle Mine). The color is produced by a their low nitrogen content.
Coiffe
A net made of gold or silver threads, decorated with gems or pearls worn on the head.
Coin Silver
A silver alloy that is 80% silver and 20% copper. Many European silver pieces are coin silver and are marked “800”, indicating that 800 parts out of 1000 are silver.
Coin-style edge
see Milgrain edge.
Collar
A necklace worn close around the neck. See also “choker”.
Collarette
A collarette (also known as a bib necklace) is a short necklace with flowing ornaments at the front.
Collet
The ring of metal that surrounds and secures the stone in a bezel setting.
Collet Setting
A collet setting is a very early method of setting gemstones. A collet 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 (the claws were not used much after the 1200’s and 1300’s.
Color
One of the 4 C s of diamond grading, the term “color” actually refers to the absence of color in a diamond. A diamond acts like a prism letting light pass through, refracting back to the human eye, into a rainbow of color. The color scale breaks up the subtlety and various grades of a diamond’s color from purest white to yellow and brown. The letters D through Z are used to designate a diamonds color with D being colorless and Z-graded stones having a lot of color.
Colored Diamond
Diamondss can be found in a full spectrum of colors. Colored or “Fancy” diamonds are simply referring to diamonds that are not white.
Colored Gold
An alloy of gold and other metals producing rose, yellow, white, and green shades.
Comfort back
A rubber or plastic pad that goes over the clip end of a clip-on earring to cushion the earlobe.
Comfort Fit
A ring that adds to the comfort of the wearer by being curved on the inside of the shank.
Commemorative Wares
Items used to commemorate an important or historical event, such as a battle, coronation, or wedding.
Compass Ring
A rotating ring that can be used to determine compass direction by using the position of the sun and the time of day.
Composite Suite
A composite suite is a piece of jewelry that can be taken apart into two or more pieces which can also be worn. For example, a necklace may be disassembled into two bracelets.
Concave
Concave simply means “curving inward”, like the inside of an egg shell. The opposite of Convex.
Conch
Conch is a marine animal (a mollusk) with a large, beautiful pearly shell that varies in color, but if often white or pink (pink is the most valued color). Queen conch has a large, pink shell. Conch shell is often used to make jewelry. Conch is made into beads and cameos. Conch has a hardness of 2.85 (it is relatively soft).
Concha
One of the ovals of a segmented silver belt or bridle. Also a reference to the belt itself. Now commonly called a “Concho Belt.” From the Spanish word “concha”, meaning “shell”.
Concho
See Concha.
Condition , Excellent
A piece of jewelry in Excellent Condition will show reasonable evidence of wear, and have a fine patina.
Condition, Fine
A piece of jewelry in Fine Condition may show slight wear, but not enough to have developed a patina.
Condition, Good
A piece of jewelry in Good Condition will show substantial evidence of wear. It will have a noticeable patina which may include numerous very fine pits or lines. It will not have cracks, chips, obviously discolored or poorly replaced stones, evidence of glue or other repairs, or other evidence of hard wear considered to be damage. Damage of any kind is separately detailed in the item description, and generally items with damage appear at very reduced prices in the Bargain section.
Condition, Mint
A piece of jewelry having no signs of wear whatsoever, including no discolored stones. A piece that is in Mint Condition is in virtually the same condition as it was when it left the manufacturer. Considering that vintage jewelry is usually 50 or more years old, and that it likely has been worn, it is obviously quite rare to find a piece that is truly in Mint Condition.
Confetti lucite
Confetti lucite is transparent plastic with glitter or other small pieces of material within it. Whimsical bangles, earrings, pins, necklaces and other jewelry have been made from confetti lucite.
Contra luz opal
Contra luz (also spelled contraluz) opals are transparent opals that show a brilliant play of iridescence only when light shines through the stone. When the light is on the same side as the viewer, the iridescence is not readily seen (this quality makes it difficult to design jewelry using these beautiful gemstones). Contra luz means “against the light.” Unlike other opals, contra luz opals are usually faceted (rather than cabochoned).
Convex
Simply means “curving outward”, like the surface of a ball. The opposite of Concave.
Copper
A common reddish-brown metallic element, copper is the only metal which occurs abundantly in large masses as opposed to small veins or nuggets that must be mined out of other rocks. It is also found in various ores such as chalcopyrite, chalcocite, cuprite, and malachite. When alloyed with tin it forms bronze, and when alloyed with zinc it forms brass. Copper is an excellent conductor of heat and electricity and is widely used for electrical wiring, as well as water piping and corrosion-resistant parts. When in moist conditions, a greenish layer forms on the outside. It has been extracted and used for thousands of years. The name is derived from the Greek “kupros” (the island of Cyprus), called “Cyprian brass”, and known by the Romans as ‘cuprum.’
Coral
Coral is a form of calcium carbonate, (like aragonite or marble), secreted in long chains by coral polyps, who live in colonies under the ocean. Coral can be found all over the world, but the bulk of coral used in jewelry making has always come from the waters off Sardinia and the coast of Sicily, in the Mediterranean. Coral comes in colors from vivid orange, red, and white, to salmon and pale pink (called angelskin coral). In jewelry making, coral is either carved into beads, cameos, and other forms, or is left in its natural branch-like form and just polished. During the mid-Victorian era large cameo brooches of coral finely carved in high-relief floral sprays or faces were popular. It used to be thought that coral protected the wearer, so it was a traditional gift to children. Since it is composed of calcium carbonate, real coral will effervesce if touched with acid. Imitation coral is made from glass, porcelain, or plastic and will not effervesce when touched with acid.
Coral
Coral is an animal that grows in colonies in the ocean. Coral polyps secrete a strong calcium structure that is used in jewelry making. Coral ranges in color from pale pink (called 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. It used to be thought that coral protected the wearer, so it was a traditional gift to children. Coral has a hardness of about 3.5 and a specific gravity of 2.6 to 2.7. Since it is composed of calcium carbonate, coral will effervesce if touched with acid. Imitation coral is made from glass, porcelain, or plastic.
Corallium rubrum
A valuable red coral introduced to the Indians by the Spanish.
Cord belt
A thick belt worn on the waist, usually with a caftan.
Cornelian
Cornelian (also called carnelian and carneole) is a reddish form of chalcedony (a type of quartz). This translucent stone has a waxy luster. The best carnelian is from India. Most commercial carnelian is really stained chalcedony. Carnelian has a hardness of 7 and a specific gravity of 2.61.
Coronet
A small or inferior type of crown worn by a person of high rank but lower than a sovereign.
Coronet setting
See Arcade Setting.
Corundum
The name of a family of stones composed of crystallized aluminum and oxygen that includes rubies and sapphires. The color of these stones depends on the oxides present in their composition. Corundum is one of the hardest minerals second only to diamonds rating a 9 on the Mohs scale. See alumina.
Cowrie Shell
The highly polished and brightly marked shells of tropical marine gastropods of the genus Cypraea, some of which are used as currency in the South Pacific and Africa. Small cowrie shells are commonly used as beads in jewelry.
Crimp Bead
Small soft metal beads that are squeezed shut to secure clasps onto the ends of cords or chains.
Crown
The upper part of a cut diamond or stone above the girdle.
Crown Glass
Crown glass is glass that contains no lead oxide. Some fake rhinestones are made from crown glass.
Crown Height
A measurement of the distance from the girdle to the table on a diamond or other cut stone.
Crystal
A fine, high-quality glass invented in 17th century England. In order to be considered crystal rather than simple glass, the product must contain at least 10% lead oxide. The lead oxide is attributed to providing the glass with extraordinary qualities of brilliance, sound and a suitable texture for cutting or engraving. Some of the finest crystal ever made is from Baccarat in France (est. 1816) and Waterford in Ireland (est. 1729).
Crystal (GLASS)
Crystal is high-quality glass containing at least 10% lead oxide. Lead added to the melt produces very clear glass resembling rock crystal. The process of making lead crystal was discovered by the English glassmaker George Ravenscroft in 1676. Crystal is colored by adding various metallic oxides to the melt.
Crystal (NATURAL)
A crystal is a solid whose atoms form a very regular structure. Some crystals include quartz, diamond, and emerald.
Crystal Habit
Crystal habit is the crystal form that a particular crystal has. The most common crystal habits are:
Prismatic – elongated with parallel sides, like emerald, tourmaline
Tabular – short and flat (table-like), like morganite
Ocatahedral – eight faces, like diamond
Dodecahedral – 12 faces, like garnet
Acicular – needle-shaped, like rutilated quartz
Platy – occurring in very thin plates, like hematite
Crystal Systems
Crystals are divided into seven crystal systems, according to their optical properties (how light bends within the crystal), plane of symmetry, axis of symmetry, center of symmetry, crystallographic axis. Within each of the systems, the cyrstals can mineralize into different crystal habits (form). The seven crystal systems are: cubic systems, tetragonal systems, hexagonal systems, trigonal systems, orthorhombic systems, monoclinic systems, and triclinic systems. For more information on crystal systems, click here.
Crystalline
A substance composed of crystals or resembling crystal in transparency, structure and outline.
Crystallize
To cause a material to form crystals or to assume both the internal structure and external form of a crystal.
Cuban Link Chain
A standard cable chain with oval shaped links that are each decorated with a twisting pattern resembling rope.
Cubic Zirconia (CZ)
A clear, hard, mass-produced gemstone cut to resemble a diamond. The mineral baddeleyite has the same chemical composition, but to become a CZ the mineral must be heated to almost 5000 degrees Fahrenheit and have an oxide stabilizer such as yttrium or calcium added to keep it from reverting back to its original form when cooled. Almost all the rough CZ’s in the market are composed of zirconium oxide and yttrium oxide, both of which are naturally white but combine to form a brilliant clear crystal. Like diamonds, the best cubic zirconia gems are colorless but colored forms are also manufactured. Vivid green CZ is sometimes referred to as C-OX, and CZ in numerous colors is frequently sold under various tradenames, such as the yellow CZ from Ceylon called “jargon”. Cubic zirconia gemstones are cut in the same fashion as diamonds, and like diamonds the size of the gemstone is usually indicated by its weight in carats. The stone can also be measured in millimeter diameter size. Because the cubic zirconia stone is so dense and solid, it outweighs a diamond of the same millimeter size, weighing 1.7 times more than a diamond of the same millimeter diameter. It is also not as hard as a diamond rating only an 8 on the Mohs scale. Natural skin oils, soap, and dirt cause a film that dulls the beauty and luster of the cubic zirconia, just as it dulls real diamonds. The best cleaning agent for cubic zirconia is liquid dishwashing detergent, but other gem and jewelry cleaners can also be used.
Cubic Zirconium
Cubic zirconium (also known as cubic zirconia) is an inexpensive, lab-produced gemstone that resembles a diamond. Cubic zirconia was developed in 1977.
Cuff Bracelet
A wide rigid bangle with a narrow opening on one side to allow the the wrist to pass through.
Cuff link
A decorative fastener worn to close the cuff of a shirt that provides holes on the cuff for the cufflink rather than closing with buttons.
Culet
The tiny flat facet on the tip of the pavilion of a cut gemstone.
Cullinan Diamond
The Cullinan diamond (also called the Star of Africa) is the largest diamond yet found, weighing 3,106 carats (roughly 1.3 pounds) in its rough form. It was mined at the Premier Mine in South Africa in 1905. This enormous gem was named for the chairman of the company that owned the mine. It was given to King Edward VII of England for his birthday in 1907. The diamond was cut (by Joseph J. Asscher of Amsterdam) into many stones, including the Cullinan I (530 carats, pendelique-brilliant shaped, the largest cut diamond in the world), the Cullinan II (317 carats, cushion shaped), Cullinan III (94 carats, pendelique shaped), Cullinan IV (63 carats, square-brilliant shaped), and many other smaller stones.
Cultured Pearl
A means of duplicating the organic process of natural pearl creation invented by Kokichi Mikimoto circa 1893. A tiny irritant like a bead, grain of sand, or a piece of mother of pearl from another mollusk can be inserted into the opening of an oyster or mollusk. This irritant becomes the nucleus of a pearl once that mollusk secretes a lustrous substance (nacre) to cover the foreign body. An oyster or mollusk can take between five to seven years to secrete enough nacre to produce a jewelry quality pearl.
Cupid’s darts
Cupid’s Darts is another name for rutilated quartz.
Curb Link Chain
A chain composed of oval-shaped links that are twisted and often diamond-cut so they lie flat.
Cushion Cut
A stone that is cut to look like a square or rectangle with rounded edges. The cut is usually multi-faceted to give the highest possible light refraction.
Cut
One of the 4 C’s of diamond grading, “cut” refers to the shape and style of a polished gem. How a diamond is cut has a lot to do with the stone’s fire and brilliance. A diamond that is cut either too shallow or too deep will not be as brilliant as a properly cut diamond.
Cut Beads
Cut beads are glass beads that have been faceted. This process makes the bead reflect and refract more light.
Cut glass
Any glass whose surface has been cut into facets, grooves and depressions by a large, rotating wheel. Wheel cutting glass was developed in the 8th century BC, but the technique of faceting wasn’t perfected until the 18th century in England. Although cutting glass is a costly and difficult process, the brilliant effects are extraordinary!
Cut Steel
Cut steel is steel that is cut with a huge number of facets and then riveted to a plate of steel (or other metal). It was widely used in jewelry during the late 18th century, including shoe buckles, buttons, bracelet, necklaces, earrings, hair ornaments, and as a setting for cameos. Early in the 19th century, cut steel quality diminished and was stamped out in strips instead of being individually cut and riveted.
Cut Stones
Common cuts include 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).
CZ
See cubic zirconia.
An earring with a drop suspended like a chandelier. Also called a “Drop Earring” or “Dangle Earring”.
Channel Inlay
A design similar to enameling in which stones, rather than melted plastic or glass, are cut to shape and set into the recesses of a piece of jewelry. Commonly seen with jewelry using mother of pearl and turquoise.
Channel Set
A style of setting in which a number of uniformly sized small stones, usually of the round cut, princess cut or baguette shapes, are set side by side in a grooved channel. Unlike most setting methods the stones are not secured individually with prongs and there is no metal visible between the stones.
Chaplet
A garland, wreath, or ornamented band worn around the head. Chaplets are made of metal with repoussé decoration or embellished with gemstones and pearls.
Charm
A pendant or trinket worn on a bracelet, earring or necklace.
Charm Bracelet
A chain link bracelet with charms attached to it. (It’s not a charm bracelet until it has charms attached.)
Charm Ring
A ring with a charm attached to the ring band.
Charoite
Charoite is a fairly recent discovery found in Russia in 1978 in the Murun mountains in Yakutia, near the Charo River. This is the only known location for this rare mineral.
It ranges in color from a light lilac to a deep purple and can be mottled with gray, white and black inclusions. The chatoyant variety in a bright deep purple, is usually considered more valuable than the non-chatoyant variety although both are used in jewelry and compliment a number of other stones.
Chasing
A method of decorating the front, (or outside), of metal objects by making indentations using shaped punches and a chasing hammer. The opposite of chasing is repoussé.
Chatelaine
French for “Lady of the House”, a chatelaine is an ornamental chain or pin worn at a woman’s waist from which dangle keys, trinkets, scissors, needle cases, pencils, purse, etc. Chatelaines may be utilitarian or beautifully decorated and made from precious materials like silver.
Chatham synthetic rubies
Chatham synthetic rubies (laboratory-created rubies) were introduced by Carroll Chatham in 1959.
Chaton
A cone shaped rhinestone or crystal.
Chaton setting
A châton setting (also called coronet or arcade setting) is one in which the stone is held in by many metal claws around a metal ring.
Chatoyancy
Chatoyancy is the 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. Chatoyant stones are cut in cabochon to maximize the lustrous effect.
Chatoyant
A stone having a changeable luster due to the way it reflects light, such as the cat’s-eye or tiger’s eye gemstones. From the French “chatoyer”, meaning to shimmer like cats’ eyes, from the French “chat” meaning “cat”.
Chenier
Chenier is fine, hollow tubing that is used in the production of some jewelry findings (like clasps and joints), and lately, in the actual production of jewelry. The hollow 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.
Chevron setting
A chevron is a design found in heraldry resembling a shallow inverted “V”. In jewelry design, a “chevron setting” is reflective of the heraldic chevron in that it is made up of lines in a shallow inverted “V” pattern.
Chinese opal
Chinese opal is a misnomer for pearl opal (a type of organic opal), moonstone, or white chalcedony
Chloride
Any compound containing a chlorine atom.
Chlorine
An abundant element which, when isolated, appears as a poisonous, greenish-yellow gas with a disagreeable odor. It occurs naturally only as a salt, as in sea-water. Chlorine is used widely to purify water, as a disinfectant and bleaching agent, and in the manufacture of many important compounds including chloroform and carbon tetrachloride.
Choker
A close fitting necklace worn tight around the neck like a collar.
Chrome
A hard, brittle, grayish white metal, fusible with difficulty and resistant to corrosion. Its chief commercial importance is for its compounds, as potassium chromate, lead chromate, etc., which are brilliantly colored and are used dyeing and calico printing. The common modern usage is for very shiny metal objects like chrome bumpers, etc.
Chrome diopside
Chrome diopside is an emerald-green colored gemstone. It is a chromium-rich variety of the common mineral diopside (Calcium magnesium silicate). Chrome diopside has a hardness of 5 to 6 and a specific gravity of 3.3 to 3.6.
Chromium
A lustrous, hard brittle, steel-blue metallic element, resistant to corrosion and tarnishing. It is used in the hardening of steel alloys and the production of stainless steels, in corrosion-resistant decorative platings, and as a pigment in glass.
Chronograph
A chronograph is a stopwatch mechanism on a watch; it can be started, stopped and reset independently from the watch.
Chrysoberyl
A rare, hard, yellow-green mineral consisting of alumina and glucina, (beryllium aluminate), in crystal form. It is popular as a gemstone for its chatoyant qualities.
Chrysocolla
Chrysocolla (meaning “golden lime” in Greek) is an opaque blue to blue-green mineral sometimes used in jewelry. It is usually cut as a cabochon. Chrysocolla (hydrated copper silicate) is found embedded in rock crystal in copper mines in the USA, Russia, Chile, and the Congo. Although Chrysocolla has been used in ornaments since the time of the ancient Greeks, it was only described mineralogically in 1968. Its hardness varies from 2 to 4.
Chrysolite
A mineral composed of silica, magnesia, and iron sometimes used as a gem. Chrysolite ranges in color from a light pea green to a deep olive green and an oily shine. It is common in certain volcanic rocks and meteorites. Mystics have claimed that this lustrous green stone drives away evil and has special healing properties. The name chrysolite has been used in the past for yellow varieties of tourmaline and topaz.
Chrysoprase
Chrysoprase is the most valued variety of the mineral chalcedony (microcrystalline quartz) that contains nickel, giving it an apple-green color. Chrysoprase is porous and translucent. It is usually cut as a cabichon, and has been used since ancient times. Chrysoprase has a hardness of 7 and a specific gravity of 2.6. Chrysoprase is mined in Australia, Russia (the Ural Mtns.), Brazil, and the western USA. Chrysoprase is sometimes called “Australian jade,” but it is not related to jade. Hard-to-detect imitation chrysoprase is made by staining agate with chromium salts.
Cigar band
A very wide band-style ring.
Cinnabar
Cinnabar is the mineral Mercury Sulfide. Its color ranges from cinnamon to scarlet to brick red and it can be translucent to transparent. It is often carved. Cinnabar has a hardness of 2 – 2.5 (very soft) and a specific gravity of 8.1 (quite heavy).
Cinnamon stone
A brown or yellowish-brown variety of garnet more properly called “essonite”.
Cire perdu
Cire perdu (French for “lost wax”) is a process of casting metal in which the original model is sculpted in wax. The wax is entombed in clay, and the wax is 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
Named after the French word for lemon, “citron”. Citrine is often incorrectly called quartz topaz or citrine topaz. A variety of quartz, citrine is found in light yellow, amber-brown, and a brilliant orange that may be confused with fine imperial topaz. Most citrine comes from South America. In ancient times, citrine was revered as a gift of the sun and believed to be a powerful antidote to a viper’s venom. Citrine is the birthstone for November.
Claddagh Ring
First crafted by Master Goldsmith Richard Joyce in 1689, it is named after Claddagh, the fishing village he lived in at the time, which overlooks Galway Bay. The ring belongs to a class of rings called “Fede” or “Faith rings”, which date from Roman times and were popular in the Middle Ages throughout Europe. Whereas “Fede” rings have only two clasped hands, symbolizing faith, trust, or “plighted troth”, Claddagh rings have two hands clasping a heart, symbolizing love, surmounted by a crown, symbolizing loyalty. The ring worn on the right hand with the heart turned outward indicates that your heart is yet unoccupied. Worn on the right hand with the heart turned inward indicates that love is being considered. Worn on the left hand the with the heart turned inward shows everyone that your heart is truly spoken for.
Clarity
One of the 4 C’s of diamond grading. Gemstones with the highest clarity contain few or no inclusions (imperfections) in the stone’s crystalline structure. Clarity is graded with a 10x magnifier. The clarity rating of a diamond ranges from FL (flawless) to I (inclusions visible to the naked eye).
Clasp
A device used to connect two ends of a necklace, bracelet or watch strap. Popular types of clasps include: Barrel, box, Lobster claw, and Spring ring clasps. (See individual listings).
Class Ring
A ring that commemorates graduating from high school. It is usually engraved with the name of the school, the year of graduation, and a gem featuring one of the school’s colors.
Claw
A claw is a metal prong that holds a stone securely in a setting.
Claw Setting
A way of securing a stone in its mount using small prongs that surround it.
Cleaning Jewelry
The safest and easiest way to clean most jewelry is with a detergent bath. Swish together warm water and any mild liquid detergent. Clean the jewelry with a soft brush while it’s in the suds, then rinse it under warm running water. Pat it dry with a soft, lint-free cloth. Avoid using brushes, which can scratch gold. Never boil gold, and avoid using ammonia, toothpaste, a powder cleanser or scouring pads. Keep gold away from chlorine, lotions, cosmetics and perm solutions, since these products may discolor or dissolve gold alloys. gemstones rarely need cleaning unless they become dirty from hand lotion, hairspray or other products. They can be cleaned using a soft cloth with mild soap and water, but rinse well. If you are using a silver or gold jewelry dip solution, most are safe for gemstones, but read the label to make sure. Do not boil gemstones. Do not wear pearls while applying cosmetics, hair sprays or perfume. It’s best not to wear pearl strands while bathing, because water can weaken the string. Wipe pearl strands with a damp cloth after each use. Do not clean cultured pearls with chemicals, abrasives or jewelry cleaner.
Clear Quartz
A colorless transparent mineral consisting of silicon dioxide in crystal form. See Quartz.
Cleavage
Cleavage is the tendency which a stone has to fracture along its crystal structure.
Clip-on
A piece of jewelry designed to be attached by means of a clip, such as a clip-back earring.
Clip-back Earring
A hinged ring with a pad, called a “comfort back”, at one end to secure the earring to the earlobe without requiring that the ear be pierced.
Cloisonné
Occasionally called “cell enameling”, it is a type of enameling in which compartments made of thin strips of metal soldered onto a metal plate are filled with powdered glass prior to firing. The glass powder melts filling the compartments with solid glass.
Closed Setting
A closed setting is one in which the back of the stone is not exposed (the metal is not cut away behind the stone).
Cloud
A form of inclusion, “clouds” are white milky areas that can found in the diamond.
Cluster
Several stones grouped together in a jewelry setting.
Cluster Brooch
A brooch developed in the 14th century in which a large central gemstone is surrounded by a cluster of smaller gemstones and pearls.
Cluster Earring
A decorative earring made up of a cluster of glass and/or metal beads and stones
Cluster Ring
A ring featuring a central gemstone surrounded by a number of smaller stones.
Cluster setting
A cluster setting is one in which small stones or pearls are set around a larger stone.
Clutch
A device that is slid along a post to secure a piece of jewelry, such as the earring back of a stud for pierced ears.
Cocktail Ring
A large oversized ring set with precious or semiprecious stones popular during the 1940s and 1950s.
Cognac Diamond
A cognac diamond is a cognac-brown diamond (having a color of C7). Most cognac diamonds are mined in Western Australia (in the Argyle Mine). The color is produced by a their low nitrogen content.
Coiffe
A net made of gold or silver threads, decorated with gems or pearls worn on the head.
Coin Silver
A silver alloy that is 80% silver and 20% copper. Many European silver pieces are coin silver and are marked “800”, indicating that 800 parts out of 1000 are silver.
Coin-style edge
see Milgrain edge.
Collar
A necklace worn close around the neck. See also “choker”.
Collarette
A collarette (also known as a bib necklace) is a short necklace with flowing ornaments at the front.
Collet
The ring of metal that surrounds and secures the stone in a bezel setting.
Collet Setting
A collet setting is a very early method of setting gemstones. A collet 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 (the claws were not used much after the 1200’s and 1300’s.
Color
One of the 4 C s of diamond grading, the term “color” actually refers to the absence of color in a diamond. A diamond acts like a prism letting light pass through, refracting back to the human eye, into a rainbow of color. The color scale breaks up the subtlety and various grades of a diamond’s color from purest white to yellow and brown. The letters D through Z are used to designate a diamonds color with D being colorless and Z-graded stones having a lot of color.
Colored Diamond
Diamondss can be found in a full spectrum of colors. Colored or “Fancy” diamonds are simply referring to diamonds that are not white.
Colored Gold
An alloy of gold and other metals producing rose, yellow, white, and green shades.
Comfort back
A rubber or plastic pad that goes over the clip end of a clip-on earring to cushion the earlobe.
Comfort Fit
A ring that adds to the comfort of the wearer by being curved on the inside of the shank.
Commemorative Wares
Items used to commemorate an important or historical event, such as a battle, coronation, or wedding.
Compass Ring
A rotating ring that can be used to determine compass direction by using the position of the sun and the time of day.
Composite Suite
A composite suite is a piece of jewelry that can be taken apart into two or more pieces which can also be worn. For example, a necklace may be disassembled into two bracelets.
Concave
Concave simply means “curving inward”, like the inside of an egg shell. The opposite of Convex.
Conch
Conch is a marine animal (a mollusk) with a large, beautiful pearly shell that varies in color, but if often white or pink (pink is the most valued color). Queen conch has a large, pink shell. Conch shell is often used to make jewelry. Conch is made into beads and cameos. Conch has a hardness of 2.85 (it is relatively soft).
Concha
One of the ovals of a segmented silver belt or bridle. Also a reference to the belt itself. Now commonly called a “Concho Belt.” From the Spanish word “concha”, meaning “shell”.
Concho
See Concha.
Condition , Excellent
A piece of jewelry in Excellent Condition will show reasonable evidence of wear, and have a fine patina.
Condition, Fine
A piece of jewelry in Fine Condition may show slight wear, but not enough to have developed a patina.
Condition, Good
A piece of jewelry in Good Condition will show substantial evidence of wear. It will have a noticeable patina which may include numerous very fine pits or lines. It will not have cracks, chips, obviously discolored or poorly replaced stones, evidence of glue or other repairs, or other evidence of hard wear considered to be damage. Damage of any kind is separately detailed in the item description, and generally items with damage appear at very reduced prices in the Bargain section.
Condition, Mint
A piece of jewelry having no signs of wear whatsoever, including no discolored stones. A piece that is in Mint Condition is in virtually the same condition as it was when it left the manufacturer. Considering that vintage jewelry is usually 50 or more years old, and that it likely has been worn, it is obviously quite rare to find a piece that is truly in Mint Condition.
Confetti lucite
Confetti lucite is transparent plastic with glitter or other small pieces of material within it. Whimsical bangles, earrings, pins, necklaces and other jewelry have been made from confetti lucite.
Continenta
Continental was a Canadian costume jewelry company that produced good-quality pieces, usually studded with colorful rhinestones.
Contra luz opal
Contra luz (also spelled contraluz) opals are transparent opals that show a brilliant play of iridescence only when light shines through the stone. When the light is on the same side as the viewer, the iridescence is not readily seen (this quality makes it difficult to design jewelry using these beautiful gemstones). Contra luz means “against the light.” Unlike other opals, contra luz opals are usually faceted (rather than cabochoned).
Convex
Simply means “curving outward”, like the surface of a ball. The opposite of Concave.
Copper
A common reddish-brown metallic element, copper is the only metal which occurs abundantly in large masses as opposed to small veins or nuggets that must be mined out of other rocks. It is also found in various ores such as chalcopyrite, chalcocite, cuprite, and malachite. When alloyed with tin it forms bronze, and when alloyed with zinc it forms brass. Copper is an excellent conductor of heat and electricity and is widely used for electrical wiring, as well as water piping and corrosion-resistant parts. When in moist conditions, a greenish layer forms on the outside. It has been extracted and used for thousands of years. The name is derived from the Greek “kupros” (the island of Cyprus), called “Cyprian brass”, and known by the Romans as ‘cuprum.’
Coral
Coral is a form of calcium carbonate, (like aragonite or marble), secreted in long chains by coral polyps, who live in colonies under the ocean. Coral can be found all over the world, but the bulk of coral used in jewelry making has always come from the waters off Sardinia and the coast of Sicily, in the Mediterranean. Coral comes in colors from vivid orange, red, and white, to salmon and pale pink (called angelskin coral). In jewelry making, coral is either carved into beads, cameos, and other forms, or is left in its natural branch-like form and just polished. During the mid-Victorian era large cameo brooches of coral finely carved in high-relief floral sprays or faces were popular. It used to be thought that coral protected the wearer, so it was a traditional gift to children. Since it is composed of calcium carbonate, real coral will effervesce if touched with acid. Imitation coral is made from glass, porcelain, or plastic and will not effervesce when touched with acid.
Coral
Coral is an animal that grows in colonies in the ocean. Coral polyps secrete a strong calcium structure that is used in jewelry making. Coral ranges in color from pale pink (called 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. It used to be thought that coral protected the wearer, so it was a traditional gift to children. Coral has a hardness of about 3.5 and a specific gravity of 2.6 to 2.7. Since it is composed of calcium carbonate, coral will effervesce if touched with acid. Imitation coral is made from glass, porcelain, or plastic.
Corallium rubrum
A valuable red coral introduced to the Indians by the Spanish.
Cord belt
A thick belt worn on the waist, usually with a caftan.
Cornelian
Cornelian (also called carnelian and carneole) is a reddish form of chalcedony (a type of quartz). This translucent stone has a waxy luster. The best carnelian is from India. Most commercial carnelian is really stained chalcedony. Carnelian has a hardness of 7 and a specific gravity.
Corundum
The name of a family of stones composed of crystallized aluminum and oxygen that includes rubies and sapphires. The color of these stones depends on the oxides present in their composition. Corundum is one of the hardest minerals second only to diamonds rating a 9 on the Mohs scale. See alumina.
Cowrie Shell
The highly polished and brightly marked shells of tropical marine gastropods of the genus Cypraea, some of which are used as currency in the South Pacific and Africa. Small cowrie shells are commonly used as beads in jewelry.
Crimp Bead
Small soft metal beads that are squeezed shut to secure clasps onto the ends of cords or chains.
Crown
The upper part of a cut diamond or stone above the girdle.
Crown Glass
Crown glass is glass that contains no lead oxide. Some fake rhinestones are made from crown glass.
Crown Height
A measurement of the distance from the girdle to the table on a diamond or other cut stone.
Crystal
A fine, high-quality glass invented in 17th century England. In order to be considered crystal rather than simple glass, the product must contain at least 10% lead oxide. The lead oxide is attributed to providing the glass with extraordinary qualities of brilliance, sound and a suitable texture for cutting or engraving. Some of the finest crystal ever made is from Baccarat in France (est. 1816) and Waterford in Ireland (est. 1729).
Crystal (GLASS)
Crystal is high-quality glass containing at least 10% lead oxide. Lead added to the melt produces very clear glass resembling rock crystal. The process of making lead crystal was discovered by the English glassmaker George Ravenscroft in 1676. Crystal is colored by adding various metallic oxides to the melt.
Crystal (NATURAL)
A crystal is a solid whose atoms form a very regular structure. Some crystals include quartz, diamond, and emerald.
Crystal Habit
Crystal habit is the crystal form that a particular crystal has. The most common crystal habits are:
Prismatic – elongated with parallel sides, like emerald, tourmaline
Tabular – short and flat (table-like), like morganite
Ocatahedral – eight faces, like diamond
Dodecahedral – 12 faces, like garnet
Acicular – needle-shaped, like rutilated quartz
Platy – occurring in very thin plates, like hematite
Crystal Systems
Crystals are divided into seven crystal systems, according to their optical properties (how light bends within the crystal), plane of symmetry, axis of symmetry, center of symmetry, crystallographic axis. Within each of the systems, the cyrstals can mineralize into different crystal habits (form). The seven crystal systems are: cubic systems, tetragonal systems, hexagonal systems, trigonal systems, orthorhombic systems, monoclinic systems, and triclinic systems. For more information on crystal systems, click here.
Crystalline
A substance composed of crystals or resembling crystal in transparency, structure and outline.
Crystallize
To cause a material to form crystals or to assume both the internal structure and external form of a crystal.
Cuban Link Chain
A standard cable chain with oval shaped links that are each decorated with a twisting pattern resembling rope.
Cubic Zirconia (CZ)
A clear, hard, mass-produced gemstone cut to resemble a diamond. The mineral baddeleyite has the same chemical composition, but to become a CZ the mineral must be heated to almost 5000 degrees Fahrenheit and have an oxide stabilizer such as yttrium or calcium added to keep it from reverting back to its original form when cooled. Almost all the rough CZ’s in the market are composed of zirconium oxide and yttrium oxide, both of which are naturally white but combine to form a brilliant clear crystal. Like diamonds, the best cubic zirconia gems are colorless but colored forms are also manufactured. Vivid green CZ is sometimes referred to as C-OX, and CZ in numerous colors is frequently sold under various tradenames, such as the yellow CZ from Ceylon called “jargon”. Cubic zirconia gemstones are cut in the same fashion as diamonds, and like diamonds the size of the gemstone is usually indicated by its weight in carats. The stone can also be measured in millimeter diameter size. Because the cubic zirconia stone is so dense and solid, it outweighs a diamond of the same millimeter size, weighing 1.7 times more than a diamond of the same millimeter diameter. It is also not as hard as a diamond rating only an 8 on the Mohs scale. Natural skin oils, soap, and dirt cause a film that dulls the beauty and luster of the cubic zirconia, just as it dulls real diamonds. The best cleaning agent for cubic zirconia is liquid dishwashing detergent, but other gem and jewelry cleaners can also be used.
Cubic Zirconium
Cubic zirconium (also known as cubic zirconia) is an inexpensive, lab-produced gemstone that resembles a diamond. Cubic zirconia was developed in 1977.
Cuff Bracelet
A wide rigid bangle with a narrow opening on one side to allow the the wrist to pass through.
Cuff link
A decorative fastener worn to close the cuff of a shirt that provides holes on the cuff for the cufflink rather than closing with buttons.
Culet
The tiny flat facet on the tip of the pavilion of a cut gemstone.
Cullinan Diamond
The Cullinan diamond (also called the Star of Africa) is the largest diamond yet found, weighing 3,106 carats (roughly 1.3 pounds) in its rough form. It was mined at the Premier Mine in South Africa in 1905. This enormous gem was named for the chairman of the company that owned the mine. It was given to King Edward VII of England for his birthday in 1907. The diamond was cut (by Joseph J. Asscher of Amsterdam) into many stones, including the Cullinan I (530 carats, pendelique-brilliant shaped, the largest cut diamond in the world), the Cullinan II (317 carats, cushion shaped), Cullinan III (94 carats, pendelique shaped), Cullinan IV (63 carats, square-brilliant shaped), and many other smaller stones.
Cultured Pearl
A means of duplicating the organic process of natural pearl creation invented by Kokichi Mikimoto circa 1893. A tiny irritant like a bead, grain of sand, or a piece of mother of pearl from another mollusk can be inserted into the opening of an oyster or mollusk. This irritant becomes the nucleus of a pearl once that mollusk secretes a lustrous substance (nacre) to cover the foreign body. An oyster or mollusk can take between five to seven years to secrete enough nacre to produce a jewelry quality pearl.
Cupid’s darts
Cupid’s Darts is another name for rutilated quartz.
Curb Link Chain
A chain composed of oval-shaped links that are twisted and often diamond-cut so they lie flat.
Cushion Cut
A stone that is cut to look like a square or rectangle with rounded edges. The cut is usually multi-faceted to give the highest possible light refraction.
Cut
One of the 4 C’s of diamond grading, “cut” refers to the shape and style of a polished gem. How a diamond is cut has a lot to do with the stone’s fire and brilliance. A diamond that is cut either too shallow or too deep will not be as brilliant as a properly cut diamond.
Cut Beads
Cut beads are glass beads that have been faceted. This process makes the bead reflect and refract more light.
Cut glass
Any glass whose surface has been cut into facets, grooves and depressions by a large, rotating wheel. Wheel cutting glass was developed in the 8th century BC, but the technique of faceting wasn’t perfected until the 18th century in England. Although cutting glass is a costly and difficult process, the brilliant effects are extraordinary!
Cut Steel
Cut steel is steel that is cut with a huge number of facets and then riveted to a plate of steel (or other metal). It was widely used in jewelry during the late 18th century, including shoe buckles, buttons, bracelet, necklaces, earrings, hair ornaments, and as a setting for cameos. Early in the 19th century, cut steel quality diminished and was stamped out in strips instead of being individually cut and riveted.
Cut Stones
Common cuts include 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).
CZ
See cubic zirconia.
