Amethyst: A common form of quartz. Amethyst is usually purple, but can range in color from pale lavender to a very deep, reddish purple and may have milky white or green inclusions. Deeper-colored amethysts are more highly valued. The name comes from the Greek for "not drunken" as wearing amethyst was believed to be a proof against becoming intoxicated. The amethyst is said to bring good luck and to radiate love. Amethyst is the birthstone for February. Some variants are Cape amethyst and Ametrine. See our amethyst earrings, bracelets, necklaces, and rings.
AB: See Aurora Borealis.
Abalone: A mollusk whose shell is pearlescent on the inside. This material can be scraped off, sliced thin, and used as inlay on a variety of jewelry, furniture, etc. These scrapings are called "mother of pearl".
Acroite: A rare, colorless type of tourmaline.
Adventurine: A common misspelling of Aventurine.
Agate: A variety of chalcedony quartz that is a very common and used often in jewelry. 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. It comes in a wide range of colors including black, gray, brown, red, green, pink, blue, white, and yellow. Agate can be flecked with color, such as Moss Agate and Tree Agate, and is often banded, exhibiting layers of quartz crystals. Agate is often dyed to enhance the color and banding. There are a variety of popular agates including onyx, Eye Agate, Blue Lace Agate, Moss Agate, Tree Agate, and White Agate. (See individual listings)
Alexandrite: A form of the mineral chrysoberyl discovered in 1830 in Russia and named after Czar Alexander II, who was then Crown Prince of Russia. Alexandrite appears to change color under different forms of light. (See Alexandrite Effect.) It looks red when viewed in candle light, green when viewed in fluorescent light, blue-green in sunlight, and reddish-purple in standard electric (tungsten) light.
Alexandrite Effect: A phenomenon in which a stone appears to be different colors depending upon the type of light it is viewed in. Many other stones, including ammolite, garnet and sapphire, exhibit the "Alexandrite Effect." Also called Dichroism
Alloy: A compound comprised of two or more metals to increase the hardness and/or luster of the resulting product. Many alloys are found in jewelry including Alpaca, Brass, Britannia Or pewter, Britannia silver, Bronze, Coin silver, Colored gold, Electrum, Gold(under 24Kt), Green gold, Nickel silver, Niello, Pewter, Pinchbeck, Pot metal, Rose gold, Stainless steel, Sterling silver, White gold, White metal, and Yellow gold. (See individual listings)
Alumina: (also called aluminum oxide). A compound of two parts aluminum and three parts oxygen which occurs naturally as corundum. Alumina is the base of aluminous salts, a constituent of feldspars, micas, etc., and the characterizing ingredient of common clay, in which it exists as an impure silicate with water, resulting from the erosion of other aluminous minerals. In a hydrated form it is bauxite. Alumina is used in aluminum production and in abrasives, refractories, ceramics, and electrical insulation.
Aluminium: An alternate spelling of Aluminum.
Amazonite: A form of jadeite named for the Amazon river where it was first found in the 19th century. It is opaque and iridescent and ranges in color from green to blue-green. It is usually set as a cabochon since it breaks easily if faceted. It can also be found in Colorado, Virginia, the Ural Mountains of Russia, Australia, and Africa. Some rare crystals are transparent.
American Ruby: See pyrope garnet.
Ammolite: (also known as Buffalo Stone, calcentine, or korite) is the fossilized shell of the ammonite, an ancient cephalopod. It can be used as a gemstone and is a gray, iridescent stone with flashes of blue, green, purple, red, or yellow. (Blues and purples are rare.) The color changes as the stone is viewed from different angles. It is only found in southern Alberta, Canada.
Amphibole: A common mineral composed of silicate of magnesium and calcium, (with usually aluminum and iron), which occurs in monoclinic crystals and comes in many varieties, each varying in color and in composition. The color varies from white to gray, green, brown, and black. Jade is a form of Amphibole.
Angelskin Coral: A highly valued pale pink coral.
Anneal: The process of hardening glass, pottery, or metal by alternately heating and pounding it.
|4||Linen or silk||Blue Topaz|
|7||Wool or copper, desk sets||Onyx|
|9||Pottery or china||Lapis|
|10||Tin or aluminum||diamond|
|12||Silk||Pearls, colored gems|
|14||Ivory||Opal, Gold jewelry|
Anodized: An "anode" is the positive end of an electrical circuit. In the anodization process, a metal object is placed in an acid bath and an electrical current is passed through the tank. The process causes oxygen atoms to bond to the surface of the metal giving it a thin protective film and a lustrous sheen. Aluminum, magnesium, titanium, and tantalum are often anodized.
Antiqued: Jewelry that has been made to look aged, having a darkened or tarnished appearance.
Anulus pronubus: See Betrothal Ring.
Apache Tears: A glassy type of obsidian found in lava flows in the southwest USA. Apache tears are usually black, but occasionally red, brown, gray, green (rare), dark with "snowflakes," or even clear.
Apatite: A form of calcium phosphate that is a clear to opaque and comes in many colors including green, yellow, blue, violet, and yellow-green (called asparagus stone). Some apatite stones are chatoyant, like the stone tiger's eye. It is usually too brittle and soft to be used in jewelry.
Aquamarine: A member of the beryl family, like emeralds. Aquamarine is transparent blue or sea-green. The name comes from a Latin phrase meaning "water of the sea." Aquamarine is found all over the world, including Brazil, Russia, Afghanistan, Pakistan, India and Madagascar. It was thought to bring its wearers knowledge, foresight and inspiration.
Aragonite: Aragonite is a form of calcium carbonate, (like coral or marble), named for Aragon, Spain, where it was first found in 1790. It is transparent to translucent and can range in color from honey-colored to pale reds, blues and greens to clear or white. It forms hexagonal crystals, pyramidal crystals, chisel shaped crystals, and other shapes. It is not often used for jewelry.
Arizona Ruby: See pyrope garnet.
Art Deco: A popular style of jewelry from the mid-1910's until the mid-1920's originating in Paris, France. Art Deco pieces are characterized by geometric lines and angular shapes, zigzags, bold colors, molded or faceted Czech glass beads, plastics (like celluloid or Bakelite) and chrome. Colored stones were utilized more, and the opaque stones such as jade, onyx and coral were set in geometric shapes. Sleek animals such as Borzoi and Greyhound dogs were featured in some designs. It started out with relatively delicate designs, and progressed to a more bold and blocky style called Art Moderne.
Art Nouveau: A classification of popular jewelry created from the late "Victorian" period through the "Edwardian" period, about 1880-1910, exemplified by a flowing style of jewelry consisting of fluid lines, sinuous curves, floral and nature themes and natural colors. A common motif features long-haired, sensual women.
Arts and Crafts: An artistic design movement that began in the late 1800s by jewelry designers who felt that their work should look handmade. Although some pieces were made of gold, silver was more commonly used to emphasize the craftsmanship of the piece rather than the intrinsic value of the components. Pieces purposely look hand-made, incorporating hammer marks and using less expensive stones like moonstone, mother of pearl, agates, or amber in simple cabochon settings. The Arts and Crafts movement also revived the art of enamel work.
Asparagus Stone: A yellow-green form of Apatite.
Assay: A test of the purity of an alloy by scraping a bit of metal from the piece and determining the percentage of gold or silver. A piece that meets the standards of purity is given a hallmark for use outside of the U.S.
Asscher, Joseph: An eminent diamond cutter from Amsterdam who cut the 3,106 carat Cullinan diamond. In 1902 the Asscher Diamond Co. developed and patented the Asscher cut.
Asscher Cut: A squarish step cut with an almost octagonal outline which enhances the fire and light of the stone. It features a small table, a high crown, wide step facets, a deep pavilion and square culet. This cut became very popular in Art Deco jewelry and was a forerunner of the emerald cut.
Aurora Borealis: Aurora borealis means "northern lights". AB rhinestones have a special iridescent finish that shines with many colors. The iridescent surface is a result of a very thin layer of metallic atoms that have been deposited on the lower surface of the stone via a process invented by the Swarovski company together with Christian Dior in 1955.
Australian Ruby: See pyrope garnet.
Austrian crystal: Trade name for lead crystal cut with precise edges and angles at the Swarovski factory, located in Wattens in the Austrian Tyrols, by a glass-cutting machine invented by Daniel Swarovski in 1895. Austrian crystals are known for their quality, brilliance, and clarity. See Crystal.
Aventurine: (sometimes known as goldstone). Often mistaken for jade, aventurine is a granular green or blue semi-translucent to mostly opaque quartz stone with mica flecks that cause a slight metallic iridescence.
Aventurine Feldspar: See Sunstone.
Aventurine Glass: A shimmering glass containing tiny copper flakes invented in Venice, Italy, around 1700.
Axis Of Symmetry: (also called a rotational axis). An imaginary line around which an object can be rotated a certain number of degrees and still resemble the original shape. When two planes of symmetry intersect, they form a straight line, which is the axis of symmetry. Symmetry is one of the factors jewelers look for when grading cut stones. See Four C's.