FACTS ABOUT TURQUOISE

One of the most popular and most used gemstones throughout history, and still today, is Turquoise. Turquoise is an opaque mineral that occurs in beautiful shades of blue, bluish green, green, and yellowish green. It has been treasured as a gemstone for thousands of years. Isolated from one another, the ancient people of Africa, Asia and North America independently made Turquoise one of their preferred materials for producing gemstones, inlay, and small sculptures.

Its only use is in the creation of jewelry and ornamental objects. However, it is extremely popular, so popular that the English language uses the word "turquoise" as the name of a slightly greenish blue color that is typical for many variations of Turquoise.

Very few minerals have a color that is so well known, so characteristic, and so impressive that the name of the mineral becomes so commonly used. Only three other minerals have a color that is used more often in common language than Turquoise - gold, silver and copper.

Turquoise Colors

Blue minerals are rare, and that is why Turquoise captures attention in the gemstone market. The most desirable color of Turquoise is a sky blue or Robin's-egg blue. Then blue to bluish-green stones are preferred, with green and yellowish-green coloring being less desirable. Departure from a nice blue color is caused by small amounts of iron substituting for aluminum in the Turquoise structure. The iron imparts a green tint to the Turquoise in proportion to its abundance. The color of Turquoise might also be altered by small amounts of iron or zinc substituting for copper in the Turquoise structure.

Some Turquoise contains inclusions of its host rock (known as matrix) that appear as black or brown spider-webbing or patches within the material. Many cutters try to produce stones that exclude the matrix, but sometimes it is so uniformly or finely distributed through the stone that it cannot be avoided. Some people who purchase Turquoise jewelry enjoy seeing the matrix within the stone, but generally, Turquoise with heavy matrix is less desirable.

Some Turquoise locations produce material with a very specific characteristic color and appearance. For example, the Sleeping Beauty Mine in Arizona is adored for its light blue Turquoise without matrix. Much of the Turquoise from the Kingman Mine, also in Arizona, is bright blue with a spider web of black matrix. Another Arizona mine, The Morenci Mine, produces a lot of dark blue Turquoise with pyrite in the matrix. Much of the Bisbee Turquoise has a bright blue color with a chocolate brown matrix. People who know Turquoise can often associate a stone with a specific mine.

Caring for Turquoise

Turquoise jewelry should be worn with care and respect. Avoid wearing it during activities that put the gem at risk and always keep it where it will not be scratched by other items of jewelry when storing it or traveling.

Turquoise is porous, with the ability to absorb liquids. These liquids can include perspiration, body oil, cleaning products or any liquid that accidentally comes in contact with. 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 soapy solution, followed by cleaning with a soft cloth that has been dampened with plain water.

Turquoise Geography

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 State, China, Chili, 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.

Physical Properties of Turquoise

The physical properties of Turquoise are important to know for its identification and for the care of Turquoise jewelry. 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.

Turquoise in the United States

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 in Arizona, New Mexico, and Nevada which have all held the position of the leading Turquoise-producing state at one time or another. New Mexico held that position until the 1920s, Nevada held the position until the 1980s, 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 where Turquoise is formed.

When Turquoise is encountered, the quantity and quality of the material is assessed and if warranted a temporary effort will be made to recover the 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 to quickly recover the Turquoise.

Turquoise Jewelry and Art

The earliest record of Turquoise being used in jewelry or in ornaments is from Egypt. There, Turquoise has been found in royal burials over 6000 years old. In North America the earliest known use of Turquoise was in the Chaco Canyon area of New Mexico, where the gem was used over 2000 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. The early Native American jewelry designs were simple, and the Turquoise was not set in metal findings.

In the late 1800s, 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 1912, 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 1970s and declined in the 1980s. 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.

Natural and Treated Turquoise

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 and the stones cut from it and jewelry made from it are special and held in the highest regard. Untreated Turquoise is hard to find, and lots of people want it for a variety of reasons and it is usually very expensive.

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 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 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.

Composite or Reconstituted Turquoise is Turquoise made from small pieces 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. This material is often called “block Turquoise” because of this manufacturing method. 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." At the same time, some vendors are glad to sell these materials and jewelry made from them because they often have an attractive appearance and a low price.

Dyed Turquoise is Turquoise that has been dyed to produce a specific or more attractive appearance. Turquoise is a porous material and easily accepts dye. Dye can also be used to produce an outrageous, unusual or unnatural 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. Dyed Turquoise is always worth less than untreated or natural versions of similar color and quality Turquoise.

Synthetic and imitation Turquoise

A small amount of synthetic Turquoise was produced by the Gilson Company in the 1980s, and some of their material was used to make jewelry. It was produced in a sky-blue color, sometimes with a gray spider webbing. It was a ceramic product with a composition similar to natural Turquoise.

Synthetic Turquoise has been produced in Russia and China since the 1970s. Both countries are prolific producers. The material is used to make cabochons, beads, small sculptures, and many other items. These synthetics are found mostly in very inexpensive department store costume jewelry, but not exclusively.

There are many different glass, plastic, and ceramic materials with an appearance like Turquoise. Many of these can easily be distinguished from Turquoise by testing their hardness, specific gravity, refractive index, or other properties.

Ending Some of the Turquoise Confusion

Howlite and Magnesite can be identified by an experienced eye and easily separated from Turquoise using a refractometer. They have different refractive indexes. But, if you are willing to do a destructive test, the blue dye used to color Howlite and Magnesite generally does not penetrate very deep. If dyed, scratching the back of a cabochon or a bead with a sharp pin will often reveal a white interior. If the piece is heavily dyed, scratching deeper or breaking an edge might be required to determine if the piece has been dyed.

 Several minerals are found where Turquoise is expected, look like Turquoise, are misidentified as Turquoise, and often enter the gem and jewelry market labeled as Turquoise. Variscite, Chalcosiderite, and Magnesite are examples. A yellow, white, brown or green color should be an immediate clue that these might not be genuine Turquoise.

Summing it Up…..

I see many imitations and misrepresentations on platforms like Etsy (as well as others) and the risk of buying fake or misidentified Turquoise (whether  by accident or on purpose) comes at a fairly high percentage. Be cautious and ask questions to the seller if you have any doubts or even just to see if there is more to know about the Turquoise you are looking at, a lot of sellers are not thorough with their descriptions or are vague on purpose.