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Tuesday, September 30, 2008

A Favorite ! ' TURQUOISE '

Turquoise is a very interesting stone because of its many types and colors. It is easy to work with, but has its limitations because it is not considered a hard stone.








There are four types of turquoise you will see in todays jewelry market, not incuding colored howlite and African turquoise jasper. A final determination has not yet been made on the quality of turquoise coming from China, but some of it is very beautiful.

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Natural - This comes directly from the mine. It is cut shaped and polished and set into jewelry. It has no man made treatment or additives other than a polishing compound that adds to its luster. Most stones in this state are very close to gem quality.




Stabilized – This is a natural turquoise usually in nugget form, but does not hold a luster. It is submerged into a stabilizing compound and dried, cut and prepared for jewelry. The turquoise has not been altered. The pores of the stone have been filled with a clear resin that makes the stone usable. This process allows for diversity of shapes and possibilities in jewelry making. Color Stabilized stones ARE altered and the color has been added by this process. This is not necessarily bad, but it has less value than a piece that is naturally colored.




Treated - This form of color enhancement has been used for thousands of years. It is done as discussed earlier by submerging into animal fat or vegetable oil and later air dried. This will not last very long.





Fake and Synthetic – Ceramics, bone, celluloid and plastic are used to imitate turquoise. Synthetic turquoise has a very natural matrix that is produced by placing stones in the synthetic “batter” .



A very common turquoise simulant is howlite. When dyed blue, with its marking, howlite is a dead ringer for some varities of turquoise.


Turquoise consists of the chemical elements copper, aluminum, phosphorus, hydrogen and oxygen in the form of water. Most turquoise is found in ‘alteration zones’ where the native original rocks have been altered thru the intrusion of other rocks from some volcanic or other thermal influence. The color of turquoise can vary from deep blue to deep green with every variation in between. Generally the more copper in the molecule, the bluer the turquoise. Iron in the stone makes it greener. More moisture will also cause turquoise to turn greener in color. Recently a variety of yellow turquoise has been coming out of China. There is now also a turquoise jasper from Africa that is flooding the market. The cream of all turquoise is still the "Sleeping Beauty" sky blue turquoise from Arizona.




Ivoryite and Magnasite, sometimes referred to as "white buffalo turquoise" is also found in the US Southwest.

All of the above shown jewelry sets have been designed and constructed by Gayle.