Some high grade Chinese or Persian stones can be quite valuable and expensive to work with. In the case of Persian turquoise, the majority was imported to the U. Government in the late s. Quality American turquoise stones from the Southwest fetch higher prices.
Folk lore and history may play a role but this is largely due to scarcity. Many of the best American turquoise mines have been mined out and are closed. In recent years, prices of American turquoise have skyrocketed.
This has led to an increased use of non-American turquoise by Native American artists. Often, it's a more affordable way to work with natural stones. Even though it was natural. Some of the stones of the Chinese Turquoise are fantastic. I mean they look like Bisbee, they look like Lander Blue. I mean, just excellent looking turquoise. But people looked down on them because it was Chinese. But now you go out there into the market, you see a lot of high end American turquoise and the price is amazing.
Sky high. Now people are looking to the Chinese turquoise. Hardness, appearance, and rarity are three major factors when valuing natural turquoise. The hardest turquoise stones are considered "gem grade". Appearance is a matter of personal taste; the color and matrix will vary drastically between different mines.
Generally speaking, darker color and a tighter matrix are considered desirable traits. Rarity refers to how much turquoise a mine produced and how much is still available for use. These liquids can include perspiration, body oil, cleaning products, or any liquid that accidentally comes in contact.
Once absorbed, these liquids can damage the turquoise or alter its color. If contact with cosmetics or potentially damaging liquid occurs, the turquoise should be washed with a soft cloth that is dampened with a very mild soap solution, followed by cleaning with a soft cloth that has been dampened with plain water.
Then, after the turquoise is dry, store it in a jewelry box away from bright light or heat. Turquoise rough: A specimen of rough sky blue turquoise in host rock from Mohave County, Arizona.
Turquoise is rarely found in well-formed crystals. Instead it is usually an aggregate of microcrystals. When the microcrystals are packed closely together, the turquoise has a lower porosity, greater durability, and polishes to a higher luster. This luster falls short of being "vitreous" or "glassy. Turquoise forms best in an arid climate, and that determines the geography of turquoise sources.
Most of the world's turquoise rough is currently produced in the southwestern United States , China , Chile , Egypt , Iran , and Mexico. In these areas, rainfall infiltrates downward through soil and rock, dissolving small amounts of copper. When this water is later evaporated, the copper combines with aluminum and phosphorus to deposit tiny amounts of turquoise on the walls of subsurface fractures. Turquoise can also replace the rock in contact with these waters.
If the replacement is complete, a solid mass of turquoise will be formed. When the replacement is less complete, the host rock will appear as a "matrix" within the turquoise. The matrix can form a "spider web," "patchy" design, or other pattern within the stone.
The physical properties of turquoise are valuable for its identification. They are also valuable information for the care of turquoise jewelry. Important properties are summarized in the accompanying table. Weathering can significantly alter the physical properties of turquoise. Weathered turquoise might still have a desirable color, but its hardness and durability are reduced.
This turquoise cannot be cut into useful cabochons or beads. Weathered turquoise is often crushed and used to make "composite" or "reconstituted" turquoise described in the " Natural Turquoise and Turquoise Treatments " section below. The turquoise group consists of five triclinic minerals. These minerals are very similar in chemical composition, crystal structure, physical properties and often in appearance.
Members of the group are: turquoise, aheylite, chalcosiderite, faustite, and planerite. Their compositions are listed in the accompanying table. Notice that the members of the turquoise group have very similar chemical compositions. In these minerals iron often substitutes for aluminum, and copper often substitutes for zinc or iron. Because they are so similar and have ranges of composition, these minerals are often misidentified.
As a result, some material sold as turquoise is actually another mineral member of the turquoise group. These pieces date from about CE and show the typical materials used in the ancient Chacoan bead and inlay industry. Public domain image from the National Park Service. Most of the turquoise production in the United States has been located in the arid southwest, and most of that production has been in or around deposits of copper. Arizona , New Mexico, and Nevada have all held the position of the leading turquoise-producing state.
New Mexico held that position until the s, Nevada held the position until the s, and Arizona is currently the leading state. Significant amounts of turquoise have been produced in California , Colorado , Utah , Texas, and Arkansas. Most of the turquoise mined in the United States is a byproduct of copper production. The large open-pit copper mines excavate down through the shallow rock units where the turquoise is formed. When turquoise is encountered, the quantity and quality of the material is assessed, and, only if warranted, will a temporary effort be made to recover the gem material.
If the value of the turquoise is worth disrupting a billion dollar mining operation, it will be mined. The mining could be done by copper company employees, but the job often goes to outside miners who come to the mine at a moment's notice, quickly recover the turquoise, and get out of the way! Turquoise jewelry: Navajo bracelets made with silver and turquoise.
Image by Silverborders, used here under a Creative Commons license. The earliest record of turquoise being used in jewelry or in ornaments is from Egypt.
There, turquoise has been found in royal burials over years old. About years ago, miners in Persia produced a blue variety of turquoise with a "sky blue" or "robin's-egg blue" color.
Currently Arizona is the most important value producer of turquoise. There are several mines in the state, two of which are renowned for their distinctive color and performance and regarded the finest in the sector: in August , the Sleeping Beauty Mine in Globe stopped turquoise mining.
Due to the increasing world market price of copper, the mine chose to ship all the ore to the crusher and focus on copper manufacturing. The cost of untreated natural sleeping beauty turquoise has increased dramatically since the closure of the mine. As of , the Kingman Mine is still operating outside the town alongside a copper mine.
Other mines include the Blue Bird mine, Castle Dome, and Ithaca Peak, but are largely inactive owing to elevated operating costs and federal laws. Morenci and Turkey Peak are either idle or exhausted. Nevada is the other major producer of the country, with more than mines producing large amounts of turquoise.
Unlike elsewhere in the US, most of the Nevada mines were mainly used for their turquoise gem and very little was retrieved as a by-product of other mining activities.
Nevada turquoise is discovered as nuggets, fracture fillings and interstices between pieces are discovered in breccias as the cement coating. A majority of the material produced is hard and dense because of the geology of the deposits of Nevada, being of sufficient quality that no treatment or improvement is required.
Although almost every state county has yielded some turquoise, the main manufacturers are in the counties of Lander and Esmeralda. Nevada has created a broad variety of colors and combinations of multiple matrix motifs, with Nevada turquoise coming in distinct colors of blue, blue-green, and green. Some of this unusually colored turquoise may involve important zinc and iron, causing the lovely tones of light green to yellow-green.
Some of the colors of blue to green-yellow may effectively be variscite or faustite, which is comparable in shape to turquoise secondary phosphate minerals. This area was regarded by the indigenous Monitu as the Turkey Country. The peninsula has six mines, all on its southwest shore, spanning an area of approximately km2 sq mi. From a historical view, the two most significant of these mines are Serabit el-Khadim and Wadi Maghareh, one of the earliest recognized mines.
The former mine is about 4 kilometers from an old temple devoted to the Hathor deity. The turquoise is discovered in basalt-covered sandstone, or was initially overlain. There are works of copper and iron in the region. Large-scale turquoise mining is not lucrative today, but Bedouin populations use homemade weapons to quarry the deposits sporadically.
Turquoise is primarily made up of copper, so it's not a big surprise to find there are also a lot of copper mines in both Arizona and Nevada. The combination of arid climates and copper rich regions make these places hot spots for good quality turquoise.
Tanner Sr. The duo are at the helm of Gallup, New Mexico's Tanner's Indian Arts , a family-run store that's been in business for over 60 years. Turquoise can be as soft as chalk or as hard as a 6 or 7 on MOH's scale — the harder and more intense colors tend to be more valuable. Another variable in valuing turquoise is comparing all-natural turquoise to 'stabilized' or 'enhanced' turquoise. Turquoise is generally a naturally soft, porous stone that sustains damage in the cutting process — only the truly rare, good stuff can be cut and shaped for jewelry without any kind of enhancement first.
A 'stabilized' stone means soft, low-grade turquoise has gone through a special process that enhances its color and hardness. The process involves putting the stone under pressure so that it absorbs a type of clear filler, either made of epoxy or plastic. The result: a harder stone that can actually be manipulated and cut, but because it required all that help, it's not super valuable. There are other types of cheap turquoise that you may have spotted in gift shops.
Reconstituted or chalk turquoise is made up of fragments of stones that are crushed into a powder and mixed with epoxy. This results in harder blocks that can then be cut into slabs or stone shapes. Then there's the fake stuff: Block or imitation turquoise is usually made of dyed plastic or produced by manipulating another stone like howlite so that it looks like turquoise. We always encourage anyone looking to purchase turquoise or turquoise jewelry to ask questions about the stones and forever say 'if you don't know your turquoise, know your turquoise dealer.
It is indeed a special stone and one to be collected and celebrated. According to Otteson, the grade makes all the difference in determining the stone's overall value.
Like other gemstones, turquoise is graded according to criteria including the 4Cs — color, clarity, cut and carat weight — but it also has other unique factors to consider, like the location of its origin. As a miner and a cutter, I have quickly learned to never get my hopes up too high when mining, because it's hard to tell how good it is until it's cut.
Gem grade turquoise will take your breath away and send your heart rate off the charts. Despite the apparent abundance of turquoise, high quality stones are actually quite scarce — so scarce in fact that in recent years, the best turquoise has been deemed " more valuable than diamonds.
Otteson says that not only is really top-notch turquoise considered more valuable than diamonds, but it can be worth much more than other types of precious stones and metals that are often considered the most coveted jewelry staples.
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