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Roger Weller, geology instructor                     

Michael Schweska
Physical Geology
Spring 2005

                                         December Birthstone-Turquoise

Turquoise is the official birthstone for December as adopted by the American National Association of Jewelers in 1912 and the Planetary stone for Aquarius, Taurus and Sagittarius. Turquoise is suggested as a gem to give on the 5th and 11th wedding anniversaries. Turquoise is 5 - 6 on the Mohs scale of hardness. Turquoise has been mined by early Egyptians since at least 6000 BC. The finest Turquoise comes from Iran but is challenged by some southwestern United States specimens. Besides Iran, Turquoise can be found in Australia, Afghanistan and other localities in the Middle East. The Aztecs mined Turquoise in an area now known as New Mexico and a Turquoise significant amount of Turquoise comes from Arizona, California and Nevada in the United States. Turquoise, or the robin's egg blue gemstone worn by Pharaohs and Aztec Kings, is probably one of the oldest gemstones known. Yet, only its prized blue color, a color so distinctive that its name is used to describe any color that resembles it, results in its being used as a gemstone. Turquoise has been, since about 200 B.C., extensively used by both southwestern U.S Native Americans and by many of the Indian tribes in Mexico. The Native American Jewelry or "Indian style" jewelry is turquoise mounted in or with silver is relatively new. Some believe this style of Jewelry was unknown prior to about 1880, when a white trader persuaded a Navajo craftsman to make turquoise and silver jewelry using coin silver. Prior to this time, the Native Americans had made solid turquoise beads, carvings, and inlaid mosaics. Click here for a picture in natural form. Click here for more faceted and natural specimens.


The color is, of course, turquoise, but this color actually varies from very green blue to light sky blue shades. The color can change with exposure to skin oils if the stone has not been stabilized and therefore, jewelry should be wiped clean to deter this. The name "Persian Turquoise" is now generally used to refer to any turquoise stone that does not have the black or brown veining commonly found in turquoise mined in the United States and used in a style of jewelry created by the American Indians. Turquoise gets its name from the French translated as "stone of Turkey". Another possibility could be the name came from the French description of the gemstone, "pierre turquin&q meaning "dark blue stone". The name Turquoise is apparently related to the fact that is was brought to Europe from the Eastern Mediterranean by Levantine traders, more commonly known as Turks.


The formula for Turquoise is CuAl6(PO4)4(OH)8*5(H2O), Hydrated Copper Aluminum Phosphate. Most specimens are cryptocrystalline, meaning that the crystals can only be seen by a microscope. Chemically, a hydrated phosphate of copper and aluminum, turquoise is formed by the percolation of meteoric material or groundwater through aluminous rock in the presence of copper. For this reason, it is often associated with copper deposits as a secondary mineral, most often in copper deposits in arid, semiarid, or desert environments.

Legends, Myths and Healing Properties:

TurquoiseA sacred stone for the North American Indians as well as the Tibetans, it is often used by shamans in rituals and ceremonies. Many Native Americans carved it into the shape of animals and birds. These carvings were placed in the Indians tombs to attract beneficial spirits and to guard the dead. Turquoise was also used by medicine men for healing and by warriors who fixed turquoise to the end of their bows to insure accurate shots. It is said to promote mental and spiritual clarity and expansion and to enhance wisdom, trust, kindness and understanding. Turquoise attracts money, success and love. Its powers include protection, healing, courage, friendship, and luck. It is also said to relax the mind, and ease mental tension.



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All rights are reserved by original sources.
Smithsonian Institute 1998-2005 Bernardine Fine Art Jewelry. 1999-2004 Jewelry Central, JC Store.
2004 Amethyst Galleries, Inc. 1995-2005 Loretta Elaine's Gems for Friends.