Ancient Turquoise Gemstones

For many Americans, turquoise seems aAfghanistan, Argentina, Australia, Brazil, China,
distinctively American gemstone -- mined inIsrael, Egypt, Mexico and Tanzania. The name
Arizona, New Mexico, Colorado and Nevada, and"Persian Turquoise" is now generally used to refer
with a long history in native American jewelry.to any turquoise stone that does not have the
But turquoise has been an important gemstone inblack or brown veining commonly found in
many eastern cultures for thousands of years.turquoise mined in the United States and used in a
This is reflected in the English name for the gem,style of jewelry created by the American Indians.
since it was first brought to Europe by tradersFrom the gemological perspective, turquoise is a
from Asia Minor. But probably the turquoise camehydrous phosphate of copper. It is fairly soft, with
from famous turquoise mines in Iran or Egypt,the hardest specimens reaching only 6 on the
not Turkey.Mohs scale. Despite its softness, turquoise takes a
Turquoise, along with lapis lazuli, is one of thevery good polish. Turquoise is always opaque and
oldest gemstone materials known to man. Thethe color varies from blue to green, sometimes
color of turquoise is so unique that this haswith flecks of pyrite or interspersed with dark,
become the standard word we use to describespidery limonite veining.
the slightly greenish shade of cyan and similarLike many gemstones, the demand for high
colors.quality turquoise exceeds the supply. This has led
The legendary home of the world's finestto the development of treatment methods to
turquoise is the mines at Nishapur in Iran.improve the color and durability of lower cost
Turquoise became a major trade and barter itemmaterial. Softer and more porous turquoise can
for the early Persians. Persian turquoise wasbe enhanced by impregnating the stone under
found in ancient graves in Turkistan and, in the 1stpressure with hot acrylic resins. The resins
to 3rd century A.D., in graves throughout theimprove the color, hardness, and durability of the
Caucasus.material. As long as the materials are represented
For centuries, the most valuable turquoise cameas treated, this is regarded as an acceptable
from Iran but today deposits are also found inpractice in the gemstone industry.