What is Enhanced Turquoise?
Enhanced turquoise means that the stones have been treated to become better than the stone’s raw state. Most raw natural turquoise is a fairly brittle and porous material. The stone’s color can fade or change over time, and the stone itself is subject to cracking. High-grade turquoise stones don’t have many of these issues, but medium to low grade stones have a serious durability and longevity problems. Enhancement usually means that some kind of chemical or physical process has been applied to the stone. Industrial processes use glues, epoxies, or resins for the stabilization of the stone. There are also processes which use dyes to enhance the color of the stone. These enhancements should be labeled properly to inform a buyer that the stone’s appearance has been enhanced. There are different levels of enhanced turquoise. The enhancement state of the turquoise is a direct correlation to the value of the gemstone.
Enhanced Turquoise. Chinese turquoise stones that have been stabilized.
The term was originally coined by the R.H. and Company of Glendale California. The company invented a revolutionary treatment called the Zachary process. The process consists of a chemical treatment and controlled heating of the turquoise stone. The Zachary process results in a harder, more durable stone, and it also increases color longevity. A secondary process of fusing vaporized quartz increases the structural integrity.
Different States of Turquoise Enhancement
Natural Turquoise
Natural turquoise is quality raw turquoise that has been cut or polished. When a turquoise stone is called natural, it has not been enhanced. This is usually the most valuable form of turquoise. However, it is rare that raw turquoise is durable enough to be used in the jewelry industry. Most turquoise on the market has been enhanced in some way to increase stability. This is called Stabilized Turquoise.
Stabilized Turquoise
Stabilized turquoise is turquoise that has been assisted by some other material to maintain its natural state. Stabilized turquoise is often misunderstood and confused with reconstituted turquoise. There are many degrees of how a turquoise stone has been stabilized, which can greatly affect its respective value. About 98% of all turquoise on the market today has undergone some kind of stabilization. Turquoise is soft and chemically absorptive, the stone’s color is susceptible to change when exposed to other chemicals. Even the oils from the human skin can effect turquoise color. If the stones are not protected, then the turquoise will change color over time.
Generally, it is acceptable to stabilize the natural color of the turquoise by coating it with protective oils and waxes or using a few complicated scientific processing techniques. These surface treatments keep the stone looking its best for years to come. Other techniques of stabilization can be poorly done that have a range of impact on the value of the original stone.
Dyed turquoise
Low grade turquoise tends to express limited color or is inconsistently hued. It is common to have lower grade turquoise stones dyed to improve their appearance. Dyed turquoise is considered less valuable because the end result is very artificial. It is common to see the use of dyes in conjunction with other stabilization processes, like the techniques used to make reconstituted turquoise.
Kingman turquoise dyed green
Infused Turquoise
Turquoise is porous and easily absorbs applied liquid substances. Turquoise that has been artificially introduced to another substance, to enhance its appearance, is called infused turquoise. For example, a new technique that is becoming more common is to enhance turquoise with a metallic bronze coating to give the matrix an extra kick. This is called bronze infused.
Bronze infused turquoise
Reconstituted Turquoise
Reconstituted turquoise is a material compound that contains real turquoise; usually chalk turquoise in conjunction with other materials such as plastics, dyes and resins. Turquoise in this state has a plastic feel to it and is often dull. This material can be molded into shapes to make it appear to look like turquoise nuggets. Technically, this material can still be called turquoise because of its color, and also because it actually contains traces of raw turquoise. But this is considered unethical for anyone selling a reconstituted stone to call it “real” or “natural” turquoise without informing the consumer of the actual state.
Block Turquoise
Block Turquoise is a type of reconstituted turquoise that is mass-produced and sold in cubical blocks. Artists can cut off and shape this material into any shape they desire. Block turquoise is often found in mass produced foreign import jewelry, because it is cheap and easy to work.
Plastic Turquoise
Plastic turquoise is 100% plastic, with no real stone inside. Because turquoise is also an official name of a color, plastic turquoise can still be marketed as turquoise. We are against this practice here at Turquoise Skies, as we feel it is confusing and misleading to the consumer. We feel it is unethical for a seller to sell plastic as turquoise without labeling the material as plastic.
Resources
Source: Fritsch, Emmanuel. McClure, Shane. Ostrooumov, Mikhail. Andres, Yves. Koivula, John. Kammerling, Robert. The identification of Zachery treated Turquoise 1999. Website pdf : https://web.archive.org/web/20230923150041/https://image1.fmgstatic.com/pdf/The-Identification-of-Zachery-Treated-Turquoise.pdf
From the Library: Pogue, The Turquois (1915)
1915 primary source. Anything described as current here describes 1915, not today.
Enhancement is not new. Pogue (1915, p. 72) translated a treatise of about 1300 describing pale turquoise that jewelers smeared with butter to darken it; the darker color was only temporary, and the trade had a name for such stones.
Writing in 1915, Pogue described the trade's view of color-treated stones at the time:
“From time to time turquoises that have had their color deepened or otherwise improved by artificial means come into the trade. As such stones are apt to revert to their original shade upon continued wear, those treated in this manner are not sold except in attempts to defraud.”
— Pogue (1915), p. 133
Pogue (1915) traced the practice back centuries:
“That the turquois may be temporarily improved in color has long been known. Muhammed Ibn Mansur in the thirteenth century mentioned that its color was strengthened by mutton fat or by smearing with butter.”
— Pogue (1915), p. 133
Citing Blake, Pogue (1915, p. 133) reported that the Pueblo Indians of the Southwest heightened the color of their turquoises by soaking them in tallow or grease.
According to Pogue (1915, p. 133), sellers near Nishapur in Persia often carried stones in their mouths before offering them for sale, and dealers in Meshed were said to keep turquoises in moist earthenware pots, because moisture temporarily improved the color of inferior stones.
On dye, Pogue (1915) wrote:
“Off-color stones are sometimes stained with Prussian blue.”
— Pogue (1915), p. 133
From the Library: Branson, Turquoise: The Gem of the Centuries (1975)
1975 primary source. Anything described as current here describes 1975, not today.
Branson (1975) described the stabilized turquoise on his plate:
“No color or dye has been added.”
— Branson (1975), p. 8
Branson (1975) explained why top-grade stone was not stabilized: the plastic
“will not penetrate compact dense material”
— Branson (1975), p. 8
According to Branson (1975, p. 8), treated chunks that were cut open showed only partial penetration: the original pale color in the center and the plasticized color outside.
Branson (1975) photographed soft pieces dipped halfway in resin:
“The tops are the original color, almost white; the lower portion shows the color change the resin causes.”
— Branson (1975), p. 8
From the Library: Lowry, Turquoise: The World Story of a Fascinating Gemstone (2010)
2010 primary source. Anything described as current here describes 2010, not today.
According to Lowry (2010, p. 196), some of the earliest recorded treatments came from Chinese cultures, who rubbed yak fat into turquoise, and Native Americans were known for soaking lower-grade turquoise in bear grease to deepen its colour. [3]
According to Lowry (2010, p. 197), so-called "kitchen treats" can mean soaking low- or medium-grade turquoise in Crisco, mineral oil or vegetable oil, or heating it in paraffin wax, then tumbling it to a polish. Lowry adds that these treatments generally reach only the surface, not the core of the stone. [3]
Lowry (2010) traced American stabilization to Globe, Arizona:
“In the United States during the 1950s and 1960s, on the sunporch of an unknown old man's home, which was located on a hillside above Globe, Arizona, Leonard Hardy and several others were introduced to "soak treating" turquoise”
— Lowry (2010), p. 197 [3]
According to Lowry (2010, p. 198), Hardy, Charlie Voight and others, advised by plastic manufacturers, first put chalk turquoise in a stainless-steel pan with electrodes at each end, added petrochemicals and blue dye, and ran electricity through the mix. They then covered the pan with tinfoil and let the sun cure it for four to six weeks. Lowry records that this "old treat" was later replaced by polyester impregnation without dyes, and that the Colbaugh family was among those who continued and refined Hardy's epoxy-bonding system. [3]
Lowry (2010) named the processes:
“Three methods are named to specifically describe stabilizing processes: simple soaking, vacuum impregnation, and high-pressure impregnation.”
— Lowry (2010), p. 199 [3]
According to Lowry (2010, p. 202), poor stabilization shows. If the resin does not fully penetrate, the centre stays whitish, and stone that was not dried first can crack, form open pockets, or come out with uneven colour or white spots. [3]
According to Lowry (2010, p. 203), James E. Zachery, who came from a turquoise lapidary family, began experimenting in the 1950s. He developed a patented process for medium-grade turquoise, not chalk, that can treat either cut cabochons or rough. [3]
From the Library: Turnbaugh, Indian Jewelry of the American Southwest (2007)
2007 primary source. Anything described as current here describes 2007, not today.
According to Turnbaugh (2007, p. 33), turquoise could be dyed, or stabilized with plasticizing epoxy, resin, oils or waxes, especially when it was a low-grade or soft stone in its natural state. [4]
From the Library: Ryan & Chambless, Turquoise in America Part Two: 1910–1990 (2020)
2020 primary source. Anything described as current here describes 2020, not today.
According to Ryan & Chambless (2020, p. 19), for most turquoise, color or hardness or both are modified to prepare it for use in commercial jewelry manufacture; their book closes with a chapter describing the various treatments. [5]
Marty Colbaugh recalled, in an interview published by Ryan & Chambless (2020, p. 165), that his grandfather got the idea for stabilizing in Globe, Arizona, in 1948, when a friend was setting scorpions and snake heads in epoxy paperweights and he tried the same with a piece of turquoise chalk, and the colour came out. [5]
Marty Colbaugh recalled, in an interview published by Ryan & Chambless (2020, p. 166), that cutters from Idar-Oberstein in Germany came to see the Kingman material and asked for all of it stabilized, because they held that natural stone could eventually turn green and chip when carved, while stabilized stone could be cut paper-thin without changing colour; they paid ten dollars a pound more for it. [5]
Bill King recalled, in an interview published by Ryan & Chambless (2020, p. 148), that he began backing thin turquoise in 1969 so it could be set without breaking, first with plastic wood and then with an auto-body filler, and that within a year backed stones were in high demand in Gallup. [5]
Ron Alexander described, in an interview published by Ryan & Chambless (2020, p. 262), how he understood Jim Zachary's process: Zachary, an electronics engineer in Texas from the Zachary turquoise family, adapted the growing of silicon crystals from circuit-board work to grow crystals inside turquoise's pores rather than filling them with an acrylic, deepening color and hardness; he patented it, and it became known as the enhancing process. [5]
Ron Alexander recalled, in an interview published by Ryan & Chambless (2020, p. 262), that by about 1989 Hardy Turquoise had just acquired the enhancing process from Jim Zachary and was applying it to Chinese rough. [5]
According to Ryan & Chambless (2020, p. 272), over 80% of turquoise must be treated in some way to have the colour and hardness needed for jewelry. [5]
Russell Twiford III, who has treated turquoise since the early 1970s, told Ryan & Chambless (2020):
“Enhancing is just stabilizing with silica, because all turquoise contains some content of silica.”
— Ryan & Chambless (2020), p. 281 [5]
Russell Twiford III told Ryan & Chambless (2020, p. 281) that enhanced turquoise was sold as natural for many years, that it gives a slightly lighter product, and that because it seemed higher grade and was accepted on QVC it sold for more; he added that enhancing usually needs harder material than chalk, whereas stabilizing works at any hardness. [5]
Russell Twiford III recalled, in an interview published by Ryan & Chambless (2020, p. 280), that in the early 1970s stabilized turquoise produced by L. W. Hardy in Kingman was all the craze, because there was not nearly enough natural turquoise to meet demand. [5]
Ron Alexander, a jeweler, dealer and developer of a turquoise treatment, told Ryan & Chambless (2020) what stabilizing does:
“You're essentially just changing the optics.”
— Ryan & Chambless (2020), p. 279 [5]
Ron Alexander told Ryan & Chambless (2020, p. 280) that stabilizing uses acrylic formulations that must be cured carefully or they shrink and show white striations, and that epoxy, which is more viscous, is used when dye is added because pigments separate out of an acrylic treatment. [5]
Russell Twiford III told Ryan & Chambless (2020, p. 281) that colour treatment adds dyes to the stabilizing process to enhance or change the colour, producing fashions such as purple, magenta and lime-green turquoise, and that dark blue epoxy-dyed stone was common when Japanese buyers wanted it. [5]
From the Library: Stacey, Turquoise Blue Book and Indian Jewelry Digest (1975)
1975 primary source. Anything described as current here describes 1975, not today.
Captioning old heishe and nugget strands, the 1975 Turquoise Blue Book noted an old treatment:
“The old necklaces are generally pure turquoise, sometimes pre-treated in hot animal fat to harden the stone and stabilize color.”
— Stacey (1975), p. 17 [6]
Joseph Stacey, writing in 1975, on how little of any find is top grade:
“With turquoise less than 10 percent of any mined quantity will qualify as virgin, pure, super-fine or gem quality. Approximately 15 percent will be judged as top grade to better than average and good.”
— Stacey (1975), p. 85 [6]
Stacey (1975) drew the line here:
“There is nothing new, dishonest or disgraceful about the treating or stabilizing of turquoise.”
— Stacey (1975), p. 85 [6]
And went on, in the 1975 Turquoise Blue Book:
“What is dishonest and disgraceful is the misrepresentation and mislabeling of jewelry using treated and stabilized turquoise at prices comparable to that of gem quality stones.”
— Stacey (1975), p. 85 [6]
From the Library: Jacka, Navajo Jewelry: A Legacy of Silver and Stone (1995)
1995 primary source. Anything described as current here describes 1995, not today.
Joe Tanner of Tanner's Indian Arts, as quoted by Jacka in 1995:
“Today, if you get one hundred pounds of turquoise, only about five pounds is naturally acceptable. Ninety percent of the turquoise today is treated [artificially enhanced].”
— Jacka (1995), p. 82 [7]
On stabilized stone, Gene Waddell told Jacka in 1995:
“And there's nothing wrong with that, if buyers are made aware of the fact that it is not natural gemstone.”
— Jacka (1995), p. 83 [7]
Jacka (1995) on oils, waxes and similar surface treatments:
“This temporarily treated turquoise will eventually fade, usually within a few days to a few months. Unfortunately, it lasts long enough for the unscrupulous seller to pass it off as a good stone to novice buyers.”
— Jacka (1995), p. 84 [7]
From the Library: Welch, Indian Jewelry (1973)
1973 primary source. Anything described as current here describes 1973, not today.
Writing in 1973, Welch gave buyers a simple warning about greased stones:
“Soaking inferior stones in grease gives them a deeper color. When these stones are left in the sun, the grease sweats out of them, and you can feel it.”
— Welch (1973), p. 53 [8]
According to Welch (1973, p. 53), inferior stones were at times shipped to Germany, dyed a deeper colour, and shipped back to the Southwest for the smiths to set. [8]
From the Library: Lund, Indian Jewelry: Fact and Fantasy (1976)
1976 primary source. Anything described as current here describes 1976, not today.
According to Lund (1976, p. 136), by 1976 nearly all stones were sold cut and polished with a black epoxy backing already attached, priced by carat weight with the epoxy included; on stabilized stones the backing added depth and weight to shallow cuts. [9]
Lund (1976) on what the backing hides:
“It also adds density to the appearance, since natural turquoise is never translucent, but stabilized and treated turquoise often is, due to the plastic deposits. Epoxy hides this fact from the buyer.”
— Lund (1976), p. 136 [9]
Lund (1976) tried to clear up the terms:
“To attempt to clear up terminology, you might say that all stabilized turquoise is treated, but not all treated turquoise is necessarily stabilized.”
— Lund (1976), p. 144 [9]
According to Lund (1976, p. 144), stabilizing as practised in 1976 used no dye but impregnated better (never top) grade turquoise with clear acrylics such as diallyl phthalate, while "treated" stones began as soft, chalky material soaked with dye and coated with plastic that often left a whitish core. [9]
Field Notes by Mateo James
Our page calls stabilization generally acceptable, but in 1915 Pogue wrote that color-improved stones were sold only in attempts to defraud, because the treatments he knew faded back to the original shade with wear. Oscar Branson, writing decades later in Turquoise: Gem of the Centuries, estimated that treated material was “possibly 80 percent of all turquoise mined” and said it should be sold as treated or stabilized. Both views are here so readers can see how the trade's standard has changed since 1915.
Our article counts coating turquoise with oils and waxes as a form of stabilization. Lowry (2010) keeps them apart: oil and wax "kitchen treats" reach only the surface, while stabilization forces resin into the stone's core under heat, pressure or vacuum. Chambless & Ryan also describe stabilization as resin introduced into chalky stone under pressure. I tend to side with Chambless & Ryan.
Lowry (2010) traces American stabilizing to a hillside above Globe, Arizona, where Leonard Hardy and others learned soak treating from an unknown old man. In Ryan & Chambless (2020), Marty Colbaugh says his grandfather worked out the idea in Globe in 1948 and was the only one doing it at the time. Both stories start in Globe; they differ on whose idea it was, and since one is a family's account, I have left both here.
This page credits R.H. and Company of Glendale with inventing the Zachary process, while Ron Alexander, in an interview Ryan & Chambless (2020) published, credits Jim Zachary himself, a Texas electronics engineer, and describes crystals grown inside the stone's pores. Lowry (2010) spells the name Zachery. These accounts don't line up, so I'm showing them side by side until a primary record, such as the patent itself, settles it.
This article gives about 98% as the share of stabilized turquoise on the market. Ryan & Chambless (2020, p. 272) give over 80% as the share that must be treated. One counts what is on the market and the other counts what comes out of the ground, but they aren't the same figure. I tend to side with Ryan & Chambless.
I notice Lois Essary Jacka, writing in 1995, described oil, wax and similar coatings as temporary treatments that fade within days to months, while the opening of this article presents protective oils and waxes as an accepted way to keep a stone's color. I show her description beside it.
I want to point out a difference in tone on this page. The article describes coating turquoise with protective oils and waxes as generally acceptable, while Welch (1973, p. 53) listed soaking stones in grease among the tricks a buyer should beware of. Pogue (1915) and Lowry (2010), quoted above, both record grease or fat used to deepen colour, so the open question is where a protective coating ends and a colour-deepening soak begins.
Our article describes stabilized turquoise as turquoise assisted by another material to keep its natural state. Lund, writing in 1976, framed it as a treatment: all stabilized turquoise is treated, though not all treated turquoise is stabilized. I note the difference and show both.
Sources
- Branson, Oscar T. Turquoise: The Gem of the Centuries. Santa Fe: Treasure Chest Publications, 1975. Cited by printed page. Statements describe conditions as of 1975.
- Pogue, Joseph E. The Turquois: A Study of Its History, Mineralogy, Geology, Ethnology, Archaeology, Mythology, Folklore, and Technology. Memoirs of the National Academy of Sciences, Vol. XII, Part II, Third Memoir. Washington, 1915. Public domain. Cited by printed page. Statements describe conditions as of 1915.
- Lowry, Joe Dan, and Joe P. Lowry. Turquoise: The World Story of a Fascinating Gemstone. Layton, UT: Gibbs Smith, 2010. Cited by printed page. Statements describe conditions as of 2010.
- Turnbaugh, William A., and Sarah Peabody Turnbaugh. Indian Jewelry of the American Southwest. Foreword by Barry M. Goldwater. Atglen, PA: Schiffer Publishing, 2007 (copyright 1996 and 2007; first published 1988). ISBN 0-7643-2577-9. Cited by printed page. Statements describe conditions as of 2007.
- Ryan, Mike, II, and Philip Chambless. Turquoise in America, Part Two: 1910–1990. Callais Press, 2020. Cited by printed page. Statements describe conditions as of 2020.
- Stacey, Joseph, ed. Turquoise Blue Book and Indian Jewelry Digest. Arizona Highways Collectors Series. Phoenix: Arizona Highways (Arizona Department of Transportation), 1975. Cited by printed page. Statements describe conditions as of 1975.
- Jacka, Lois Essary. Navajo Jewelry: A Legacy of Silver and Stone. Photographs by Jerry Jacka. Flagstaff: Northland Publishing, 1995. Cited by printed page. Statements describe conditions as of 1995.
- Welch, Frankie. Indian Jewelry: How To Wear, Buy and Treasure America's First Fashion Pieces. McLean, VA: EPM Publications, Inc., 1973. Cited by printed page. Statements describe conditions as of 1973.
- Lund, Marsha Mayer. Indian Jewelry: Fact and Fantasy. Boulder, CO: Paladin Press, 1976. Cited by printed page. Statements describe conditions as of 1976.
