TREATED TURQUOISE
Drilling, grinding and carving turquoise has always presented problems to Native American Craftsmen. Turquoise is a relatively soft stone (roughly 7 on the hardness scale) and it tends to crack and break while being worked. Long hours and great skill are required to drill and gring natural turquoise. The old hand drill method, with the turquoise placed under water to keep it cool, is probably still the most effective way to control breakage and loss.
However, many methods of treating turquoise to make it easier to cut and work have developed over the years. One of the earliest was to soak the stone in bear grease. Hot parafin was another treat often used to facilitate grinding and drilling. This also enhanced the depth of color of the turquoise.
In recent years, much more sophisticated methods of hardening or stabilizing turquoise have been developed. One such method was created by L.W. Hardy, one of the pioneers in this field. Hardy's technique is to soak the softest and most absorbent turquoise (known as chalk to those in the trade) in an oil based chemical. After several days of soaking, in an air-tight container, the chalk is then removed, wrapped in foil, and placed in a large pressure cooker.
As a result of this process, this otherwise soft and relatively unworkable turquoise becomes a stone which can be easily sliced, ground, drilled and carved, with much less loss in both time and turquoise to the craftsman.
At roughly one-fifth the price per pound of natural turquoise, this savings in money, time, and breakage allows the carvers and bead makers to produce a finished piece of jewelry at a much lower cost, which they can pass on to their customers.
Turquoise which has been stabilized in this manner is generally accepted in certains forms of jewelry, most notably Santo Domingo and Zuni carvings and in heshi making as long as it is represented as such. Stabilized turquoise when set in silver, however, is generally viewed as being less desirable since the turquoise is not as intricately worked and hence the loss factor is not as great.
Some of the finest Native American craftsmen still insist on working only with natural turquoise. They feel the quality of the final product is worth the extra time and expense. This view is widely held among knowledgeable collectors who feel that stabilized turquoise does not tend to hold its value as an investment.
To the average buyer, however, the cost of owning a piece of natural turquoise heishi, for example, may seem high when balanced against some of the fine pieces of jewelry created from good quality stabilized turquoise. As long as the turquoise is represented correctly, the choice is ultimately the consumer's. | 
