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ABOUT TURQUOISE  Turquoise has fascinated humankind throught history. The earliest turquoise mining operations were located in the Sinai Peninsula and worked by the ancient Egyptians in about 5500 BC. The turquoise mines of Persia have produced some of the world's finest turquoise. The earliest mention of turquoise in Persia is in a story about the mine of Isaac, the father of Israel, who lived about 2100 BC. The use of turquoise in Tibet is thought to have begun very early as their word for it is totally original and not borrowed from any other language. Turquoise was used very early on in China and is still used today. In the SouthWest, turquoise mines were worked by Native Americans before the time of Christ. Many of the mines that are still producing today were worked in prehistoric times. TURQUOISE FORMS Turquoise is found in a number of different forms including: Turquoise deposited in cracks in rocks to form vein turquoise, Turquoise formed in a cavity lined with quartz crystals, Turquoise formed as nuggets, and Turquoise formed in cracks in rock to form flattened or disc-shaped nuggets. Turquoise generally forms in arid climates such as the American Southwest. it is usually marketed by the name of its mine. SPIDER WEB TURQUOISE: Spider web is made up of small nuggets cemented together with natural rock or matrix. When cut through, the aggregate mass of nuggets resembles spider web. Most mines produce some spider web turquoise. SEA FOAM TURQUOISE: Sea Foam is a descriptive term recently applied to a kind of knobby, foam-looking nugget that can be polished without cutting, except for flattening the back to mount in jewelry. Many mines have produced this type of nugget, but it has not been popular until the new term "Sea Foam" appealed to the buyers.  KINDS OF TURQUOISE FOUND ON THE MARKET NATURAL TURQUOISE: Turquoise found naturally in the earth. Natural turquosie can deepen in color over time by gradually absorbing oils from the skin. STABILIZED TURQUOISE: Best recognized by its transparent plastic appearance. It is too blue and too highly polished. Stabilized turquoise can be easily scratched with a hard knife blade. High quality turquoise cannot be scratched with a knife. Stabilized turqoise is soft, low quality turquoise which has been soaked and cured in clear epoxy resin. This creates a deeper blue and much tougher stone. It does not change the hardness. High quality turquoise cannot be treated or stabilized as the plastic will not penetrate compact dense material. Can be beautiful and a good buy as it is not as expensive as natural turquoise. TREATED TURQUOISE: Soft turquoise that has been stabilized with clear epoxy resin and also dyed. Colors look more artificial. Sould be priced much less than natural or stabilized turquoise. RECONSTITUTED TURQUOISE: This is low grade turquoise that has been gound to powder, saturated with epoxy resin, dyed, compressed into blocks or cakes and then cut. Should be very inexpensive. IMITATION TURQUOISE: The plastic and glass turquoise stones are easily recognizable. Mineral-based compositions, usually pressed or molded together with a plastic type binder, are soft enough to be easily scratched with a knife blade. Synthetic turquoise, known as Luroc, is reportedly the same chemical composition as natural turquoise with about the same hardness. It is usually very smooth and highly polished. NATIVE AMERICAN TECHNIQUES The Navajo silversmith usually starts with the turquoise stone and designs the article of jewelry around it.  The Zuni almost always construct the silverwork first and then cut the stones to fit the spaces.  The Hopi work mostly in overlay, a method employing a sheet of silver with cut out designs soldered over another sheet of silver. They place the emphasis of design on the silver rather than on the turquoise. CARING FOR YOUR TURQUOISE Turquoise is a porous stone that should be cleaned with a soft, damp cloth and patted dry. Do not use soap. Do not soak in water. ultrasonic cleaners should not be used as they can damage the stone. Powdered magnesium carbonate can be sprinkled on the stone, left to sit for a short while, and then brushed off with a soft brush. Apply deodorants, makeup, perfume and hairspray prior to putting on your turquoise jewelry as all can cause damage to the stones. Remove turquoise rings before doing dishes or swimming as soap and/or chlorine can damage the stones. Exposure to extreme sunlight or heat may cause cracking of the stone or color change. Store in a cool, dry place. |
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