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ABOUT TURQUOISE — ROYAL GEMSTONE OF THE AGES
 Turquoise is one of the oldest gems known to man, and has been prized by humans for thousands of years for use in jewelry and carvings. One of the oldest known examples are the turquoise bracelets found on the First Dynasty Egyptian Queen Zar who ruled some 7,500 years ago. In addition to the ancient Egyptians who mined turquoise in the Sinai Peninsula for many centuries, the cultures of early Persia (now Iran), Tibet, and China also mined the rock and valued it highly. This gold necklace with turquoise, gray chalcedony and glass, is from Iran, late 14th to early 15th century C.E. (photograph ©1989 The Metropolitan Museum of Art).
Turquoise is a complex copper mineral, which is characteristically found in arid regions associated with copper deposits. Turquoise is classified as a hydrated phosphate of copper and aluminum having the chemical formula of CuAl6(PO4)4(OH)8.4H2O. It is formed when groundwater percolates through rocks containing an abundance of copper, aluminum and phosphate and then is redeposited as a secondary mineral. Consequently, it is most commonly associated with copper deposits in arid or desert areas.
Early Turquoise Mining in the New Mexico and Arizona Southwest
Becky uses gems and semi-precious stones from all over the world in crafting her jewelry. From the beginning, her main focus has been on turquoise, especially domestic turquoise mined in the American Southwest, where she lives. In the American Southwest, turquoise was mined by the prehistoric Native American cultures at least a thousand years ago from mines located in New Mexico and Arizona. Archaeological discoveries in Mexico and Guatemala suggest that this turquoise was traded as far south as Central America, where it was used extensively by the Aztecs. Most of the literature about the mining of turquoise in New Mexico by prehistoric Native American cultures references the Cerrillo Mines in north-central Mexico with a connection to the Chaco Canyon Anasazi Culture. In Southern New Mexico, it is known that in the Burro Mountains (just 15 miles southeast of the Casitas de Gila) and in the Hachita Mountains (about 70 miles south of Casitas de Gila) turquoise was mined by the prehistoric Native American Mogollon or Hohokam cultures hundreds of years before both of these areas became important turquoise producers in the 1880s and early 1900s.
 Some of the best turquoise ever mined in New Mexico came from the Burro Mountain deposits.
In 1891, the Azure Turquoise Company organized in New York and began developing the Azure Mine in the Burro Mountains. The Azure Mine produced a very hard, robin’s-egg-blue turquoise that was claimed to be comparable to the finest Persian turquoise, the standard for gem quality at the time, and was guaranteed not to change color or fade. By 1907, the Azure Mine was reported to have produced several million dollars of gem turquoise, a very substantial sum in those days! The Burro Mountain turquoise mines ceased activity around 1910. In the early 1900s, Phelps Dodge Mining Company acquired all of the property on which the Burro Mountain turquoise deposits were located and began a large-scale, open-pit copper mining operation at Tyrone in 1967. In 2007, the Phelps Dodge holdings were purchased by Freeport-McMoRan Mining Company.
Largely because of the economic success of the Azure Mine and the Tiffany Mine in the Cerrillos District, by 1909 New Mexico turquoise had moved from having trinket value to gem status. After 1910, supply and demand plus the vagaries of fashion guided turquoise production in the Southwest through several boom and bust cycles, with numerous small mining operations opening and closing throughout Arizona, New Mexico and Nevada. Today, largely due to depleted deposits, steadily increasing economic and environmental constraints, plus competition from major turquoise mining operations in China, there are only a few turquoise producing mines left in the American Southwest.
Seeking Authentic Southwest Turquoise
Over the past 14 years Becky and her husband, Michael, who is a geologist, have been going to the Tucson Gem and Mineral Showcase, one of the largest gem and mineral trade shows in the the world, held annually in late January and early February. During this time they have watched the availability and variety of quality Southwest turquoise decrease significantly while the price increased geometrically. At the same time, less expensive Chinese turquoise has flooded the marketplace. While Chinese turquoise can be of high quality, often it is not, nor is it what it is represented to be. Since a significant portion of the turquoise market is devoted to the fashion trade, where color and stone shape are the main considerations, many second and third tier sellers have no idea as to the source or type of processing of the turquoise they are selling. Nor do they care to know.
Another factor, which complicates the issue even more for the novice turquoise buyer, is the fact that only about 5% or less of the turquoise coming from the mines today and ending up on the market is a completely natural stone, hard enough to be made into jewelry without further processing. The other 95% must be stabilized with various types of acrylic, sodium silicate or epoxy to give the stone durability plus the ability to take a high polish and not change color or absorb oils from the wearers skin. While stabilized turquoise may be frowned on by the purest, it is an acceptable industry practice … as long as it is disclosed by the seller that the stone has been treated in this manner. And, of course, it makes the stone more affordable.
Unfortunately, such disclosure is often times not forthcoming, nor does it stop there. Many poorer grade turquoise deposits yield considerable amounts of very pale colored chalky material, so in addition to the stabilization process artificial color is added to make the stone more attractive. An even lesser grade turquoise stone is produced by taking dust, small chips or pieces of otherwise unusable material, adding a color dye and then “reconstituting” it with epoxy and compression … sort of like making a turquoise tater-tot! Then there is the bargain basement of the turquoise marketplace where you will encounter so-called “turquoise” that is actually a soft, white, chalky mineral such as magnesite or howlite that has been dyed and stabilized; or, need we mention, the blue-green 100% pure plastic imposters!
Under such market conditions, it is imperative that the seeker of good quality and genuine Southwest turquoise know from whom they are purchasing. For these reasons Becky only buys her turquoise material from reputable miners and dealers who know their product and will guarantee it.
Presently, Becky is using both natural and stabilized turquoise in her jewelry
from these Southwest mines:
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Sleeping Beauty: Located at Globe, Arizona, yielding both natural and stabilized turquoise which has a uniform robin’s-egg-blue color with little or no matrix. Considered by many to be the standard by which other mines are judged. This mine ceased operation in 2012. The price of the remaining turquoise available has skyrocketed since then. |
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Kingman: Another actively-producing mine located near Kingman, Arizona, yielding both high quality natural and stabilized product in several varieties and grades ranging from deep blue to blue-green with or without matrix minerals such as pyrite. Considered a classic turquoise stone. |
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Royston: An active small-scale, mine with limited production located in southwestern Nevada, yielding deep green to light blue colors, often together with a dark brown to gold colored matrix. |
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Emerald Valley: This active small-scale mine is located in southwestern Nevada near the Royston deposits and is a dark green to greenish blue with a complicated matrix. |
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Castle Dome: This mine, located near Globe, Arizona closed in the early 1970s. Current stones are available in limited quantities from old stockpiles. This stone is characterize by its bright blue to pale blue colors with a light brown to gold matrix. |
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Fox: This mine, located in Lander County near Crescent Valley, Nevada, is now reportedly closed but stone is still available from old stockpiles. Color is green to blue green with a distinctive matrix. |
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Morenci: This mine located in Morenci, Arizona, is now closed; however, material is still available from old stockpiles. The color ranges from light to dark blue and is often characterized by an irregular matrix of pyrite that polishes to a silvery luster. |
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Nacozari: This mine is located south of Bisbee, Arizona, in Sonora, Mexico. It has a pale to bright blue color with very little matrix material. |
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Campo Frio: This mine is located in the Cananea area of northern Sonora, Mexico. It is a green to sky blue color with light brown to gold-colored matrix. |
Turquoise from Non-Southwest Sources
  While most of Becky’s turquoise jewelry uses authentic material from the American Southwest, some of her pieces do incorporate high-grade Chinese and Tibetan turquoise. The reason for this is that some of the colors, matrix materials, and textures from these sources are exceptionally unique, and lend themselves to the creation of very distinctive jewelry which would not be possible from Southwest turquoise. As with the domestic turquoise, over the years Becky has developed a good relationship with several reputable dealers of Asian turquoise who guarantee the quality of the material they sell. While some of the Asian turquoise she uses is stabilized, none is dyed, most is totally natural, and often times the stones have been shaped by hand. All of Becky’s jewelry comes with full disclosure as to the country of origin and as to whether the turquoise is natural or stabilized.
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