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About Turquoise
Properties and Occurrence of Turquoise
Turquoise's color ranges from sky blue to green. It has a hardness of 6 or slightly more than window glass. Color variation of Turquoise is a result of the mineral's chemical properties, ranging from white to a powder blue to a sky blue, and from a blue-green to a yellowish green.
Turquoise was among the first gems to be mined, and while many historic sites have been depleted, some are still worked to this day.
For at least 2,000 years, the region once known as Persia, has remained the most important source of turquoise, for it is here that fine material is most consistently recovered. Iranian turquoise is considered superior in its color and hardness.
The Southwest United States is a significant source of turquoise; Arizona, California, Colorado, New Mexico and Nevada.
New Mexico is thought to be the location of the oldest mines; prior to the 1920s, the state was the country's largest producer; it is more or less exhausted today.
Arizona is currently the most important producer of turquoise by value, with the vivid Bisbee Blue being a good example of the state's natural endowment; much of the Arizona material is recovered as a byproduct of copper mining. Currently the only two active Turquoise mines in the world exist in the state. The first is the Kingman Turquoise Mine which was started up again on the back of the copper mine in the area. The other is the Sleeping Beauty Mine found near Globe.
History of its use
Turquoise has captured the hearts of many cultures of antiquity since before 4000 BC: It has been adorned by rulers of Ancient Egypt, Aztecs, Mexoamericans, Perisa, Mespotamia, China etc.
A common belief shared by many of these civilizations held that turquoise possessed certain prophylactic qualities; it was thought to change colour with the wearer's health and protect him or her from untoward forces.
Legend has it that the Indians believed that if turquoise was affixed to a bow, the arrows shot from it would always hit their mark. It was also believed to bring happiness and good fortune to all.
Imitations
Howlite is often dyed to imitate turquoise. Turquoise made in a laboratory has a very uniform color. Chalky varieties of turquoise are often coated with wax or oil to enhance color - and when treated like this, the color change is not permanent.
Turquoise is often fracture sealed. This doesen't mean that it has fractures, it means that it was sealed with an acrylic resin to enhance it's color, texture, and hardness.
Turquoise is somewhat soft so avoid scratches and sharp blows. To be certain and coatings are not removed also avoid hot water and household chemicals.
Reputable dealers will not use the following misleading terms. However, for your protection, I am listing them here:
"Vienna turquoise" is really a glass imitation. Turquoise is found in Australia, Chile, Iran, Mexico, Tibet, USA (Arizona , California and New Mexico).
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