Probably one
of the most recognized semiprecious gemstones in existence, turquoise has
been popular since prehistoric times. This stone is a hydrated aluminum copper
phosphate that often contains iron. Its name comes from French pierre turquoise,
meaning "Turkish stone," a reference to where Persian material passed on its
way to Europe. It is considerably softer than quartz and thus is usually treated
in some way for stability. It occurs naturally in shades ranging from sky
blue to grey-green, usually in locations where copper is hidden in the soil
in high concentrations. The blue color is caused by copper, while the green
color is caused by iron or chromium. Many qualities and types of "turquoise"
are available on the market today.
High-grade
natural turquoise is the hardest grade and takes the best polish.
Many mines produce stones with distinctive color or matrix whose origin can
be identified by an experienced person.
Enhanced
turquoise is the common name for medium-grade turquoise treated by
a proprietary process that impregnates and hardens the stone with vaporized
quartz. The process will not work on low-grade "chalk" turquoise and is undetectable
by normal testing methods. (For details, please see the Spring 1999 issue
of Gems & Gemology.)
Stabilized
or treated turquoise is treated with a plastic resin. Most nugget
and some heishi products are made from real turquoise that has been stabilized.
Stabilization allows genuine but lower-grade turquoise to be used in jewelry.
Even when a stone has been stabilized, its color can be changed over time
by pollution, soap, skin lotion and oil.
Wax-treated
turquoise: Much of the turquoise from China is wax impregnated. The
process works like stabilization. The paraffin treatment only affects the
surface.
Reconstituted
turquoise: This term describes small pieces of stone mixed with blue
dye and plastic binder. Most products marketed under this name should really
be labeled as "simulated block."
Block
turquoise: A mixture of plastic resin and dyes that is produced in
loaf-size blocks. This turquoise contains no actual rock of any sort. Block
is used heavily for inlay, heishi and beads. It is sometimes mistakenly called
"reconstituted."
Imitation
and simulated turquoise: Several stones can be dyed to look like turquoise,
including howlite, magnesite and dolomite. Glass, plastic, faience ceramic
and polymer clay also can look like turquoise.
Turquoise has
been mined for eons, since at least 6000 B.C. Early Egyptians wore the stone,
and many turquoise pieces have been found in their tombs. The ancient Aztecs
in Northern Peru used to decorate their ceremonial masks with this stone,
which they considered holy. Persian philosopher Al Kazwini wrote that "the
hand wearing a turquoise and using it as a sealing stone will never be poor."
Turquoises were used to decorate turbans, often set in a border of pearls,
to protect the wearer from the evil eye. The gemstone did not reach Europe
until the Crusades.
Turquoise is
considered a stone of wholeness, promoting the sense of unity of the self
and oneness with all that surrounds us. It is said to make one feel at home
in both the physical and spiritual worlds. Turquoise is said to open all chakras,
permitting the attributes of love, completeness and communication to flow
through the body and increasing spiritual bonding. It is especially connected
to the fifth (throat) chakra and is believed to assist in opening the fourth
(heart) chakra. It also is believed to assist the absorption of nutrients
while strengthening the immune system and stimulating tissue regeneration.
Crystal healers recommend it for detoxification of alcohol, poisons or radiation.
Turquoise is mined in the U.S.A. (Nevada, Arizona, New Mexico), China, Peru,
Mexico, Persia (Iran), Tibet, Siberia, Africa, Australia and Europe.
AA-grade Turquoise
This is high-grade
natural turquoise. The stone is usually from the Sleeping Beauty mine in Arizona,
and it becomes processed into beads in India, China or Vietnam. Be aware that
it will absorb body oils and, over time, become green.
A- to B-grade Turquoise
This is commercial-quality
turquoise from various sources. Beads in this category are usually stabilized
or enhanced to harden the stone. Our -002 items are rarely color-enhanced,
although the stabilization process deepens the color (just as a wet sponge
is darker than a dry one). These beads are produced from rough turquoise mined
in China, Mexico or the United States (at the Kingman mine in Arizona). These
beads are produced from Chinese, Mexican or American rough turquoise. They
are well-made beads, uniform in shape and size at a median price. This makes
them a good, less-expensive substitute for Sleeping Beauty turquoise (AA-grade).
Be aware that the color will slightly darken with wear as the stone absorbs
body oils.
African Turquoise
This stone is
not true turquoise, but actually a natural jasper found in Africa. It has
a matrix structure similar to that of turquoise, and is a light bluish-green.
The matrix is usually dark or black. It is an interesting substitute for a
true turquoise.
Apple Green Turquoise aka Mojave Turquoise
Fresh-picked!
One of our newer gemstones, apple green turquoise gets its lush color from
dye applied to natural blue turquoise. Its surface is waxy and speckled like
a real apple's skin, and its color is so intense, you can almost taste it!
This gemstone is resin-stabilized and has a beautiful brown, white and dark
green matrix. Our apple green turquoise is similar to but nicer than the stone
marketed as "Mojave turquoise" (which appears to be scraps of real turquoise
bound with dyes and plastic resin, then compressed into a block). Apple green
turquoise is mined and enhanced in China.
Block Turquoise
This is manmade,
imitation turquoise, from a material known as block.
Chinese Turquoise
This category
is a variety of Chinese turquoise beads mined and processed in the Hubei provence
in mainland China. Most Chinese turquoise is enhanced, which can include wax
treatment, resin stabilization and/or dye.
Lime Turquoise
The perfect
accessory for sipping margaritas! We believe that this gemstone from China's
Hubei province is a magnesite (Mg CO3) or similar white stone that has been
dyed green. Some of the beads display a very light matrix, while others show
none. Lime turquoise is harder and cut better than the typical true turquoise
from Hubei.
Mexican Turquoise
These turquoise
beads have good color (various shades of blue and green) and a light matrix.
They are very unique in that they are found as free-form nuggets in clay material,
rather than in rock veins. They come from the Pino Chueco ("Crooked Pine")
mine in Sonora, Mexico. The mine has produced this turquoise, with color similar
to the famed Sleeping Beauty turquoise, since the mid-1980s. The beads have
been stabilized.
Yellow Turquoise, Hard aka Flower Jasper, Flower
Turquoise, Chinese Howlite
The harder version
of the two stones known as "yellow turquoise", this stone is more likely a
jasper or serpentine. However, we don't think this stone is dyed or enhanced.
It is yellow with brown, green and red, much more varied than the dyed Hubei
product (below).
Yellow Turquoise, Soft
From China's
Hubei province, this soft stone is a natural turquoise but is usually dyed
to achieve its deep yellow hue. We also believe it is wax-treated to harden
the surface, or possibly stabilized with a resin.
