Natural, Stabilized, Treated, Fake, and Synthetic
Turquoise
An article by Lee Anderson
This article discusses various types of turquoise as they relate
to the jewelry industry.
Natural
This turquoise comes directly from the mine. It is cut, shaped,
polished, and set into jewelry. Perhaps it had only been drilled,
polished, and suspended on a necklace. In any event, the stone has
had no man-made treatment or additives other than the polishing
compounds to set off its luster. Most stones used in their natural
state are very good to gem quality — in other words, hard
and dense, with an inherent luster that does not lessen as it is
exposed to its natural setting.
Stabilized
This is a natural turquoise, usually in nugget form, that is too
porous or soft to hold a luster. It is therefore submerged into
a stabilizing compound, frequently an epoxy resin. The natural capillary
action of the porous stone draws this stabilizing compound throughout
the stone. It is then dried. When thoroughly dried, it can be cut,
drilled, cabbed, etc., and prepared for jewelry. Please note that
the turquoise has not been altered; rather, the pores of the stone
have been filled with a clear resin that makes the stone usable.
If this type of turquoise were not on the market, many, many, jewelry
artisans would be unemployed. It allows wide diversity. For example,
necklaces of tiny turquoise beads now can be made and tiny inlay
is possible. Colors will not change because the pores are sealed.
It is not practical to use a high-grade natural stone for heishe;
too much turquoise is wasted in the grinding, and the resultant
bead will be fragile and eventually change color.
On the other hand, some stabilizing compounds can have color added.
This causes the turquoise to assume a color that is not naturally
inherent to that stone. This is referred to as “color shot”
or “color stabilized,” a misleading term that implies
the natural color is “stabilized.” This, of course,
is not true; color has been added. This practice is not necessarily
bad. Jewelry-making is an art, and this color enhancement can improve
the appearance of the piece. It goes without saying that the value
is less than that of naturally colored turquoise.
Treated
This form of color enhancement has existed for thousands of years.
Pogue discusses writings on this subject that pre-date Christ. A
common treatment is to submerge the stone in animal or vegetable
oil and later air-dry it to give it a luster that did not previously
exist. Unfortunately, this luster will not last long, and wearing
the piece will likely leave oil stains. Many sellers have had to
leave the area shortly after making such a sale! Even today, some
turquoise merchants submerge the stone in water to enhance its color
and weight.
Fake and Synthetic
People have been faking turquoise for centuries using ceramics,
bone, color-enhanced minerals, and more recently, celluloid and
plastic, among other things. This “fake” turquoise not
much of a problem now, as people are simply too familiar with turquoise.
However, “synthetic” turquoise, frequently chemically
perfect, has appeared on the market in some quantity. This is literally
stove-top turquoise. It has a very natural matrix created by placing
stones in the “batter” or sprinkling in pyrite, etc.
When the mix is cut, then cabbed, these foreign additives, which
are real, add to the illusion that the entire stone is natural.
Synthetics become fake if not properly identified.
References / Recommended Readings
John Adair, The Navajo and Pueblo Silversmiths, University
of Oklahoma Press, 1944.
Margery Bedinger, Indian Silver, Navajo and Pueblo Jewelers,
University of New Mexico Press, 1973.
M.G. Brown, Blue Gold, The Turquoise Story, Main Street
Press, Anaheim, CA, 1975.
Larry Frank, Indian Silver Jewelry of the Southwest, Schiffer
Publishing Ltd., Westchester, Pennsylvania, 1990.
The International Turquoise Annuals, vol. I and II, 1975
and 1976 (only two published) Impart Pub, Reno, NV. Note in vol.
I the article on pages 31–55 by D. Allen Penick, “Turquoise,
the Mineral that’s an Accident.”
Carl Rosnek and Joseph Stacy, Skystone and Silver, Prentice
Hall, Englewood Cliffs, New Jersey, 1976.
Joseph E. Poque, Ph.D, The Turquoise, A report to the
National Academy of Science, vol. XII, Second and Third Memoir,
1915. Reprinted in 1974 by Rio Grande Press, Inc., Glorieta, NM.
(This reprint includes a foreword and details on Southwestern turquoise
mines by Rex Arrowsmith and an excellent reference list. )
Stuart A. Northrop, Turquoise and Spanish Mines in New Mexico,
University of New Mexico, Press, 1975.
Stuart A. Northrop, David L. Newman, David H. Snow, Turquoise,
reprinted by General Printing and Paper Co., Topeka, KS. A reprint
from El Palacio, vol. 79, No. 1, 1973, Museum of New Mexico.
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Related Indian Jewelry Articles by Lee and Eric Anderson
• “The
History of American Indian Jewelry”
• “The
Squash Blossom Necklace”
• “Turquoise
in Indian Jewelry”
• “How
the Quality of Turquoise Affects Its Use in Jewelry”
• “Stones
Used In Indian Jewelry”
• “The
History of Turquoise”
• “The
Origin and Occurrence of Turquoise”
• “The
Physical Properties of Turquoise”
• “Turquoise
Quality”
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