Turquoise has been of interest to even early man. In the Western hemisphere in the burial sites of prehistoric peoples the stone was found.
The Anasazi and Hohokam mined turquoise throughout the Southwest. Turquoise is known to be a popular trade item because it was found hundreds of miles away from the mining sites of New Mexico in Mexico with the Aztecs.
It seems that turquoise was considered a stone of life and good fortune and had healing properties. In Egypt, the earliest known use of turquoise and the first mines of Sinai, it was mentioned as having mystical powers and was used in the art figures and ornaments.
In India it was used in art, medicine, and jewelry. In Tibet every Tibetan carried or wore a piece of turquoise all their life. In North and South America the stone was used in religion, art, trade, treaty negotiations as well as for jewelry. It was considered to be associated with life itself.
It was thought to prevent injury through accident, prevent blindness, by placing on the eyes or ground into a slave and as a powder. It was ingested to cure stomach disorders, internal bleeding, and stings from snakes and scorpions.
Their colors could forcast the good or bad, predict the weather and influence dreams. It was good for almost any ailment including insanity.
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.
Placing turquoise in animal fat can change the stone to a deeper color. Dipping it in water can also alter the color. These methods are only temporary though.
There are 4 types of turquoise you will see in the jewelry market
- 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 in 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”
Gem The 5 tests of grading must be met hardness, luster, color, matrix and rarity Less than 1% of turquoise is legitimately called a gem. Stones of the very high grade are nearly perfect
- Very High Grade -have the same general characteristics as the gem, but the matrix pattern may not be perfectly balanced. About 3% of all turquoise is this very high grade
- High Grade Turquoise of this grade is used in most high but not competition grade jewelry. It is hard, but not perfectly balanced. It could be a very attractive piece, but could be a little better. Luster must be perfect. About 5% of turquoise fits this grade.
- Jewelry Quality - This has a good hardness, a good feel, and be hard enough to not need stabilization. It must have a nice luster, but not as much as Gem thru high quality. Matrix pattern is attractive, but may not be balanced. About 10% of turquoise is in this category.
- Mine Run, Average Quality, Good Quality, and Stock - average turquoise that does not have to be stabilized because it will hold its polish, and be attractive. Stabilizing will however strengthen this quality for carving or permanence. About 20% of turquoise is this grade.
- Chalk, Bulk, Chip Stock, Levirate (as in leave it right there) Soft porous, brittle of little value to the jewelry until stabilized. Color enhancing is frequently done. Most turquoise is in this category.
Today the value of turquoise ranges from a few cents per carat to over $50 per carat for a superb gem stone.
The rarity factor is the price discriminator. A beautiful 5 carat cabochon of deep blue turquoise with a tiny spider web matrix from Lander Nev. (closed many years ago) has a retail value of $300 to $500. A similar cabochon from the Lone Mountain Mine also closed, would be $200 to $300. It is every bit as good, but it is produced for a longer time. A similar cabochon from China or Tibet that is a superior grade would be nearer $50 because the mine is still active and the turquoise is not properly publicized. A good general rule on pricing fro the different grades are:
$$$: High grade natural - $100
$$: Stabilized turquoise - $50
$: Reconstituted turquoise - $20
In Santa Fe and the rest of New Mexico the Indian Pueblos are the places you can get true turquoise at different grades, but the design are all unique to the pueblo or the artists style, so that in itself has value.
In Santa Fe in the Plaza under the Palace of the Governors the Indians will sit out on the ground and sell their designs. This is straight from the source.
Silver Sun Gallery is also a great source of knowledge and high quality turquoise.
Turquoise regarded as our nations “National Stone” has been coveted, romanced, fought for, and owned with pride so if you are a turquoise lover or shopper you are not alone.