The turquoise happens in the form of vein or seam fillings and as compact nuggets, most of which are tiny in number. 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. Miners face a danger of flash flooding in the rainy summer months; mortality from the fall of the haphazardly utilized sandstone mine walls is not unheard of even in the dry season.
The color of material from Sinai is typically greener than material from Iran, but is believed to be stable and relatively durable. For at least 2, years, Iran has been a major source of turquoise. The black turquoise was used in Iranian architecture to cover the palace towers as its intense red color was also a sign of heaven on earth. This sample is obviously black and becomes green owing to dehydration when heated.
A battered and crushed trachyte is the host of the turquoise, discovered both in situ between limonite and sandstone strata and between the scree at the top of the mountain. 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. This material was very popular and traded through Asia and into Europe. This is the source of the term "Persian Blue" color. In North America the earliest known use of turquoise was in the Chaco Canyon area of New Mexico, where the gem was used over years ago.
Ancient artists produced beads, pendants, inlay work, and small sculptures. Rough turquoise and turquoise objects were held in high regard by Native Americans and were traded widely. This spread North American turquoise across the southwest and into South America.
These early Native American jewelry designs were simple, and the turquoise was not set in metal findings. In the late s, Native American artists began using coin silver to make jewelry.
This work evolved into the turquoise and sterling silver style of Native American jewelry that is popular today. The demand for turquoise and turquoise jewelry rises and falls over time. In , turquoise was named as one of the original modern birthstones for the month of December. This gave the gem a small boost in popularity which continues to the present.
In the United States there was a surge in turquoise demand that began in the s and declined in the s. Demand for turquoise jewelry is always highest in the southwestern states where turquoise mining and Native American artists make turquoise a distinctive part of the local culture. It consists of a central pyrite mirror, which has since oxidized, surrounded by a mosaic depicting four dragons. The design is an inlay work made of slate, coral, shell, and turquoise.
The photograph is a public domain image by Jebulon. Only a small amount of turquoise that is mined today can be used to cut finished stones or make jewelry without some type of treatment.
These treatments make the turquoise stable enough for cutting, durable enough for jewelry, or improve its color and marketability. Untreated turquoise is a rare commodity. The rough, the stones cut from it, and jewelry made from it are special and held in highest regard by many people.
Untreated turquoise is hard to find, and lots of people want it for a variety of reasons. The different types of turquoise, based upon their treatments, are described below. They are listed from top to bottom in order of their desirability. Natural Untreated Turquoise is the name for turquoise that is fashioned into cabochons, beads or other items and used to manufacture jewelry without any type of treatment.
It is the most highly desirable type of turquoise, especially when it has an attractive color. You are most likely to find it for sale in stores that specialize in fine turquoise jewelry, those that sell high-quality one-of-a-kind items, or those that specialize in natural, untreated gems. Sellers of natural untreated turquoise frequently use the fact that no treatment has been done as a selling point.
Stabilized Turquoise is the name used for turquoise that has been impregnated with a polymer or other binding material to make it durable enough for cutting and use in jewelry. Straight from the mine this turquoise is too soft, too porous, too fractured or too fragile for manufacturing.
Stabilized turquoise can be cut into beautiful beads and cabochons. It is the most common type of turquoise in today's gem and jewelry market.
It is widely accepted because the supply of natural turquoise is much smaller than the demand from people who want it. The fact that an item is made from stabilized turquoise should always be disclosed to the buyer prior to sale, and the price should be lower than untreated turquoise of similar quality.
Composite Turquoise: These earrings are made with composite turquoise. Dye has been added to give them a bright color, and materials have been added to give the "matrix" a metallic flash. Composite or Reconstituted Turquoise is made from small pieces of turquoise that are mixed with a polymer and cast into block-shaped pieces.
Finely crushed turquoise and some non-turquoise materials are sometimes included. The blocks are then sawn into small pieces that are used to cut cabochons, beads and other items. Sellers who pride themselves on selling only natural gems frequently decline to sell reconstituted turquoise. Some gem identification labs decline to call this material "turquoise" and instead label it as a "man-made product.
Dyed Turquoise is exactly that. Turquoise is a porous material and easily accepts dye. The dye is used to modify the turquoise to a more marketable color. Dye can also be used to produce an outrageous color. Composite and reconstituted turquoise are the most commonly dyed materials. Dye can be used to color the turquoise or to color the polymer binding material.
Sometimes black or brown dye is used to alter the color of matrix material to make it more obvious and uniform. View All Videos View Minerals. The Mineral turquoise. Turquoise is an antique ornamental stone, highly regarded for its unique and striking namesake color. Valued in both the ancient Persian and Native American civilizations, it still retains its popularity today.
Turquoise specimens are often polished or sliced for collectors, and may even be dyed. Turquoise is porous and has a naturally waxy luster ; it is sometimes impregnated with a plastic lubricant for to enhance its luster and increase its stability. Many Turquoise fakes exist. The most prevalent is white Howlite dyed blue to resemble Turquoise. Turquoise often contains embedded shiny Pyrite flakes, or may contain black oxide veins running through it.
It is sometimes intergrown together with other secondary copper materials, especially Chrysocolla. Turquoise may also form as a pseudomorph of other minerals such as Apatite , Beryl , and feldspar s.
For additional information, see the gemstone section on Turquoise. Eilat Stone. Kingman Turquoise. Let us know how we can update this page Click for more details. We strive for accurate content and locality information. If you feel any of the content is incorrect, or if you feel we are missing vital locality information, please fill out the form below so we can update the site. If you are requesting a locality be added, please only include significant locality occurences for the mineral.
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