AB: See Aurora Borealis. Gem description taken from the aura seen around the North Pole called the ‘northern lights’.
Abalone: Also called ear shell – An edible marine mollusc (or mollusc) whose shell is pearlescent on the inside. This material can be scraped off, sliced thin, and used as inlay on a variety of jewellery, furniture, guitars, etc. These scrapings are called “mother-of-pearl”.
Abalone from Papua New Guinea
Genuine Mother of Pearl Inside view of an abalone shell. This highly prized mollusk is fished in coastal waters in both the Northern and Southern Hemispheres. All of the flesh is edible.
Acroite: An uncommon variety of tourmaline that is colourless.
Acrostic jewellery: A popular kind of jewellery during the Victorian era where the first letter of the name of each stone spells out a word. See Regard.
Acrylic Jewelry: This is contemporary jewellery made with a plastic material that is used in sheet, rod or liquid resin form. The material can be moulded when heated, or cut into various shapes, and can have a glossy or matt appearance. It can have a very wide colour range. It has been used in jewelry since 1970. Today it is often seen in beading used in the fashion industry and also as beading on chandelier lights.
Adamantine: Having a diamond-like luster or hardness.
Adder Stone: This is a highly absorbent stone that was formerly believed to be of help to draw out the poison, as from a snake bite. These stones were set in finger rings and worn as an amulet.
Adularia: A common type of moonstone, usually set as a cabochon. It is semi-translucent with a white and blue tint. Adularia was very popular in Art Nouveau jewellery.
Adriatic Jewellery: Jewellery made during the 16th-17th centuries in Italy along the Adriatic coast and in the neighbouring Greek islands. They often used cloisonne enamelling. Ship pendants and crescent-shaped earrings were common.
Adventurine: A common misspelling of Aventurine.
Aegirine: An intensely green mineral that is related to Jadeite and Acmite, but its crystals have blunt ends rather than pointed.
African Emerald: An African Emerald is not actually an emerald. It is green fluorite mined in South Africa.
African Jade: African jade is not really jade, but a type of garnet strongly resembling jade that is mined in South Africa.
Agate: A semi-precious gemstone. A variety of chalcedony quartz is very common and used often in jewellery. When chalcedony is variegated with spots or figures, or arranged in differently coloured layers, it is called agate; and if by reason of the thickness, colour, and arrangement of the layers it is suitable for being carved into cameos, it is called onyx. It comes in a wide range of colours including black, grey, brown, red, green, pink, blue, white, and yellow. Agate can be flecked with colour, such as Moss Agate and Tree Agate, and is often banded, exhibiting layers of quartz crystals. Agate is often dyed to enhance the colour and banding. There are a variety of popular agates including onyx, Eye Agate, Blue Lace Agate, Moss Agate, Tree Agate, and White Agate. Historically, Agate was used extensively in Egypt and Rome, in ornamental pieces and in jewellery such as beads and brooches.
Agatized Coral: a fossilized coral that is partly replaced by chalcedony. It is made into jewellery in cabochon form and is sometimes dyed pink or blue.
Agent: A businessman who acts for, or in the place of, another to buy or sell merchandise in exchange for a commission. Also called a “Broker” or a “middleman”.
Agrafe: A clasp or fastener for a cloak, in the form of a hook sewn on one side of the garment, to be attached to a loop or ring on the other side.
Aigrette: A feather-shaped piece of jewellery worn in the hair or on a hat. From the French word “egret”, a white heron prized for its plumage.
Alabaster: A white, opaque or translucent form of the mineral gypsum which is usually white or grey in colour. It is often used in sculpture, stone panelling, beads, and cabochons.
Albite: A common white feldspar composed of a silicate of alumina and soda. It is a common constituent of granite and of various igneous rocks.
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 colour under different forms of light. (See Alexandrite Effect.) The mineral Chromium contributes to its unique colour. 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 colours 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
Allochroite: A dark colored common garnet composed of iron lime.
Alloy: A compound comprised of two or more metals to increase the hardness and/or lustre of the resulting product. Many alloys are found in jewellery 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)
Almandine: The most common kind of garnet. It is transparent and often deep crimson with fingers of purple to red-brown and composed of alumina iron. It is not unlike a ruby in colour. The main sources are Sri Lanka, Alaska, and India.
Alpaca (alpacca): A silver substitute alloy consisting of 55% copper, 20% nickel, 20% zinc, and 5% tin.
Alumina: (also called Aluminium oxide). A compound of two parts aluminium and three parts oxygen 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 aluminium production and in abrasives, refractories, ceramics, and electrical insulation.
Aluminium: An alternate spelling of Aluminum.
Aluminum: An inexpensive, lightweight, silver-white ore with a bluish tinge. Aluminum is primarily found in bauxite, is remarkable for its resistance to oxidation, and is used in many alloys.
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 colour 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.
Amber: The fossilized resin derived from extinct coniferous trees. The most common colours are honey yellow and various shades of red, but can also be off-white, black, and blue. Amber is easily simulated using plastics, but real amber produces static electricity when rubbed. Amber is soft but tough, and so is often intricately carved and sometimes faceted. There are two main varieties – 1. Sea Amber is washed up along certain shores, especially the Baltic Sea and the shores of Eastern England. 2. Pit amber which has been mined in various places e.g. Burma and Mexico.
American Ruby: See pyrope garnet.
Amethyst: Semi-precious gemstone. A common form of quartz. Amethyst is usually purple, but can range in colour from pale lavender to a very deep, reddish purple and may have milky white or green inclusions. Deeper-coloured 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 radiate love. Amethyst is the birthstone for February. Some variants are Cape amethyst and Ametrine.
Ametrine: A mixture of amethyst and citrine, it is partially purple and partially orange-yellow.
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 grey, iridescent stone with flashes of blue, green, purple, red, or yellow. (Blues and purples are rare.) The colour changes as the stone is viewed from different angles. It is only found in southern Alberta, Canada.
Amorial: Engraved crest or coat-of-arms.
Amorini: Cupids or cherubs used in decoration. Depicted in the Bible made from silver and gold.
Amorphous: A gem lacking a distinct crystalline structure such as amber, ivory, jet, opals and glass.
Amphibole: A common mineral composed of silicate of magnesium and calcium, (with usually aluminium and iron), which occurs in monoclinic crystals and comes in many varieties, each varying in colour and in composition. The colour varies from white to gray, green, brown, and black. Jade is a form of Amphibole.
Amulet: A pendant or charm carried as a protection from evil or illness or to bring good luck.
Andradite: A garnet used as a gemstone of the grossular family consisting of calcium iron silicate and having any colour ranging from yellow and green to brown and black.
Angelite: A pale blue variety of calcium sulphate. (A gypsum that has lost water and is transparent to translucent).
Angelskin Coral: A highly valued pale pink coral.
Animal Jewelry: Articles of jewellery whose principal decorative motif is of an animal. It may be pendants, brooches, earrings, rings. There can be a very wide range of animals from dolphins to monkeys. Jewellery in the Victorian era was often made with such animal motifs. They are very popular today, especially in regions where animal welfare has become part of the culture. Very often made from Sterling Silver, Gold or plated with Gold or White Gold.
Anklet: A bangle or bracelet worn around the ankle instead of the wrist. Anklets tend to be slightly larger than bracelets.
Anneal: The process of hardening glass, pottery, or metal by alternately heating and pounding it.
Anniversaries: The chart below lists the most recognized traditional gifts and jewellery used to commemorate wedding anniversaries:
|4||Linen or silk||Blue Topaz|
|7||Wool or copper, desk sets||Onyx|
|9||Pottery or china||Lapis|
|10||Tin or aluminium||diamond|
|12||Silk||Pearls, coloured gems|
|14||Ivory||Opal, Gold jewellery|
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. (an electrolytic bath) The process causes oxygen atoms to bond to the surface of the metal giving it a thin protective film and a lustrous sheen. This oxide surface that has formed on the metal can then accept dyes. The resulting colours are dependent upon minute variations in the thickness of the oxide layers. Aluminium, magnesium, titanium, and tantalum are often anodized.
Antique Jewellery: Jewellery made more than 100 years ago.
Antiqued: Jewellery that has been made to look aged, having a darkened or tarnished appearance.
Antiquing: Darkening the recessed areas of gold or silver jewellery to enhance the visibility of engraving.
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, grey, green (rare), dark with “snowflakes,” or even clear.
Apatite: A form of calcium phosphate that is clear to opaque its many colours 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 jewellery.
Applique: An ornamental object which was produced separately and then applied to a piece of jewellery.
Aqua Aura: Quartz crystals coated with a fine layer of gold, aluminium, or copper, which gives them a beautiful iridescent blue finish.
Aqua Regia: A 3:1 mixture of hydrochloric acid and nitric acid used to test gold and platinum. It is one of the few substances that can dissolve gold or platinum.
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 colour from honey-coloured 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 jewellery.
Arcade Setting: (Also called coronet or châton setting). This refers to when a gemstone is set in a metal ring and secured by many metal claws.
Arctic Opal: This is not an actual opal, but a blue-green stone mined in the Wrangle and Chugach Mountains of Alaska that is a mixture of azurite and malachite.
Arizona Ruby: See pyrope garnet.
Arizona Spinel: A garnet found in Arizona that resembles a spinel.
Arkansas Diamond: Not a real diamond but a form of clear rock crystal.
Arkansas Stone: An abrasive used to smooth metals in jewellery making.
Art Deco: A popular style of jewellery from the mid-1910’s until the mid-1930’s originating in Paris, France. Some of the popular artists were Cartier and Van Cleef & Arpels, collectors also look for the work of Georges Fouquet’s son, Jean (1899-1984). Art Deco has some popularity again in the 1960s and 1970s. Then from around 2009 there was another surge in prices for these pieces. 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 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 jewellery created from the late “Victorian” period through the “Edwardian” period, about 1880-1910, it featured a free-flowing style of jewellery consisting of fluid lines, sinuous curves, floral and nature themes and natural colours. A common motif features long-haired, sensual women. There was a surge in the popularity of Art Nouveau jewellery around 1980-1990’s. Then in 2010, Christie’s Geneva’s sale of a Lalique [1860-1945] necklace bought 327,000 CHF (Swiss Franc).
Rene Lalique. Popular as a glassmaker, Lalique created chandeliers, jewellery, vases, perfume bottles and clocks.
Articulated: Jewelry constructed with hinges to make it flexible.
Arts and Crafts: An artistic design movement that began in the late 1800s by jewellery 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 handmade, 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. Today there are many many artists who design, make and sell their own style of jewellery. This is very evident in the popular street-side markets around the world.
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 jewellery and was a forerunner of the emerald cut.
Asterism: A star-like luminous effect caused by reflections of light in some stones, like Star Sapphire and Star Garnets.
ATW: Stands for the Approximate Total Weight, in carats, of a gemstone.
Aurora Borealis: Aurora Borealis means “northern lights”. AB rhinestones have a special iridescent finish that shines with many colours. 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. Found in Brazil, India, Japan, Russia and USA.
Aventurine Feldspar: See Sunstone.
Aventurine Glass: A shimmering glass containing tiny copper flakes was invented in Venice, Italy, around 1700.
Aventurine Quartz: A type of quartz found in India, Russia, and Tanzania that contains sparkling flecks of mica or iron.
Awabi Pearl: The Japanese name for Pearls found in abalone molluscs.
Axinite: An unusual, lustrous stone that is bi-coloured in brown, yellow, blue, green or grey. Violet axinite, from Tasmania in Australia, is rare. It is used only as a mineral specimen and not in jewellery.
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 jewellers look for when grading cut stones. See Four C’s.
Aztec Jewelry: Articles of pre-Columbian jewellery made by the Aztec Indians.
Azurite: A copper-based mineral that is often used in jewellery ranging from very deep blue to pale blue. Azurite is also used as a dye for paints and luxury fabrics.
Azurite Malachite: Malachite is often found in the same mineral deposits as azurite. Azurite Malachite is simply a mineral that contains both forms of stone and has bands of light and dark blue.