Briolette: A pear-shaped or oval gem, especially a diamond, cut in long triangular facets. Brushed Finish: A textured finish on jewelry, where a series of tiny parallel lines are scratched on the surface of the metal Carat: Faceted Gems are measured in carats. One carat equals 0.2 grams. There are about 142 carats in an ounce. A carat is further divided into hundreds, or points. Stone Sizes and Weights. Cubic Zirconium: Called CZ, is a diamond imitation with high dispersion and refraction, weighing 70% more than a diamond. CZ looks great in 10kt, 14kt and 18kt gold settings. CZ has great color and hardness not far from a diamond. Cultured Pearls: Pearls that are produced by inserting a mother-of-pear bead into a live oyster and then returning it to the water; usually into "farming beds" to grow its nacre coating. DEEP CUT: Many gemstones are deep cut to enhance the color and to add weight to the stone. DIAMOND: Diamonds are precious, lustrous gemstones made of highly-compressed carbon. Diamonds 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. Colors of diamonds range from colorless, yellow, orange, brown, to almost black. Rarer colors are red, blue, green, and purple. A diamond's value is based on the "4 C's": color, cut, clarity, and carat weight. A diamond's color is rated on an alphabetical scale ranging from D (white) to Y (yellow). A diamond's cut is designed to maximize the stone's natural "fire"; A diamond's clarity depends on the number and size of its flaws and inclusions (of other minerals, like quartz). Clarity is rated from FI (flawless), IF (flawless at 10x magnification), a series of V ratings (very small flaws at 10x magnification), a series of S ratings (small flaws at 10x magnification), to I1, I2, and I3 (having inclusions visible to the naked eye). A diamond's carat weight is simply how much it weighs (a carat is about 0.2 grams or about 0.007 ounces). EMERALD:
Emeralds are a very hard, green precious
stone (beryl) colored by chromium and some vanadium impurities).
Flaws and cloudiness (called jardin) are very common in
emeralds, so many emeralds are oiled, irradiatied,and dyed to
improve their look. Synthetic emeralds (developed by Carroll
Chatham in the 1930's) have fewer imperfections and are very
hard to distinguish from natural emeralds. Emeralds belong the
beryl group of stones which also includes aquamarines,
morganite, and chrysoberyl). Emeralds have a hardness of 7-8 and
a specific gravity of 2.6 - 2.8. Emerald (and all forms of
beryl) have large, perfect, six-sided crystals. Emeralds were
long thought to have healing powers, especially for eyesight.
During the renaissance, emeralds were used as a test for
friendship among the aristocracy; an emerald given to a friend
would remain perfect as long as the friendship endured.
Gold: Gold Standards Gold is a precious metal that has been valued by people since ancient times. People use gold for coins, jewelry, ornaments, and many industrial purposes. Until recently, gold reserves formed the basis of world monetary systems. Gold is a very soft metal when it is pure (24 Kt. is pure gold). Gold is the most malleable (hammerable) and ductile (able to be made into wire) metal. Gold is usually alloyed (mixed with other metals, often silver and copper) to make it less expensive and harder. The scientific abbreviation of gold is Au. Gold 24 hour spot chart Italian Jewelry: Italian Jewelry is well known for its quality, design, and craftsmanship. ONYX: Onyx is a semi-precious stone that is black and white, generally arranged in layers. It is a form of agate with parallel banding. This structure lends itself to cameo making. Onyx is a species of chalcedony (microcrystalline quartz). OPAL: Opals are semi-precious stones that are luminous and iridescent, frequently with inclusions of many colors ("fire"). Opal is a mineral composed of noncrystalline (amorphous) silica (and some water) and is a species of quartz. There are three major types of opals: common opal, opalescent precious opal (white or black, with a rainbow-like iridescence caused by tiny crystals of cristobalite), and fire opal (a milky stone that is fiery orange to red in color with no opalescence). Contra luz opals are transparent opals that show a brilliant play of iridescence only when light shines through the stone. Many opals have a high water content - they can dry out and crack if they are not cared for well (opals should be stored in damp cotton wool). Opals have a hardness of 5.5 to 6.5 and a specific gravity of 1.98-2.50. Opals are found in many places worldwide, including Kenya, Czechoslovakia, Brazil, Peru, Honduras, Mexico, Canada, and the USA -- but Australia has a tremendous variety of beautiful opals. Platinum: Platinum is pure, an expression of integrity, a reflection of inner truth. Platinum's purity endows it with a brilliant white luster. This helps to reflect the true radiance of diamonds. Because it is generally 95% pure (18 karat gold is 75% pure), platinum jewelry does not fade or tarnish and keeps its looks for a lifetime. Platinum's purity makes it hypoallergenic and ideal for those with sensitive skin. Platinum is rare, the coveted treasure of discerning individuals. There is very little platinum on this earth and it is found in very few places around the world. This exquisite metal is 30 times rarer than gold. In fact, it is estimated that if all the platinum in the world were poured into one Olympic swimming pool it would be scarcely deep enough to cover your ankles. Gold would fill more than three pools. Platinum's rarity makes it exclusive and distinctive - a celebration of your individuality. Platinum jewelry is the perfect choice for a lifetime of everyday wear. Its density and weight make it more durable than other jewelry metals. Platinum does not wear away and holds precious stones firmly and securely. Like all precious metals, platinum scratches. However, the scratch on a platinum piece is merely a displacement of the metal and none of its volume is lost. So, even though wearing it each and every day may leave an impression on the surface, it remains what it was - a symbol for all things eternal. In addition to its strength and density, platinum has another remarkable quality - pliability. Platinum is so pliable, that just one gram of the metal can be drawn to produce a fine wire over one mile (almost 2 km) long. This quality has enabled jewelers to create some amazing versatile platinum mesh accessories, which could not be fashioned from other precious metals. Platinum is also in demand in other fields - it is used in industry, most notably in catalytic converters. Platinum also plays an important role in medicine. It is not affected by the oxidizing reaction of blood, has excellent conductivity, and is compatible with living tissue. Because of these properties, platinum is used for pacemakers. At present, more than 50,000 people are living healthily on pacemakers. Platinum is a life-saving metal for these people. Platinum 24 hour spot chart RUBY: Rubies are precious stones and a member of the corundum family . Rubies range in color from the classic deep red to pink to purple to brown. Rubies are extremely hard; only diamonds are harder. During the renaissance, people thought that rubies could counteract poison. Laboratory-produced rubies were created in the 1890's; they are difficult to distinguish from natural rubies. Rubies have a hardness of 9 and a specific gravity of 3.9 - 4.1. Rubies are found in Afghanistan, Australia, Brazil, Cambodia, India, Myanmar (Burma), Malagasy Republic, Malawi, Pakistan, Sri Lanka (Ceylon), Tanzania, Thailand, United States, and Zimbabwe (Rhodesia). SAPPHIRE: Sapphire is a precious gemstone (a type of corundum) that ranges in color from blue to pink to yellow to green to white to purple (mauve sapphire) to pink-orange (padparadscha sapphire). Six-sided asterisms sometimes occur in star sapphires (caused by inclusions of tiny, thin, parallel needles of rutile). Sapphires are related to rubies. Sapphires were once thought to protect the wearer from poisonous creatures. Sapphire has a hardness of 9 and a specific gravity of 3.9 - 4.1. Sapphires are often heat treated to improve their color. Sterling Silver: 92.5% silver (usually the other 7.5% is copper). It must be at least 92.5% silver to be classified sterling. Silver 24 hour spot chart Synthetic Gems: Artificial gem materials that are reproductions of natural gems. TOPAZ: Topaz (aluminum silicate fluoride hydroxide) is a very hard gemstone that ranges in color from brown, to yellow to blue to pink. Pink topaz is usually created by irradiating common yellow topaz. Other colors are often created by heat-treating and/or irradiating topaz. Imperial topaz is golden orange-yellow topaz; it is the most valuable topaz Topaz has a hardness of 8 and a specific gravity of 3.5-3.6.
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