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This Red Scare Is Real

By David Federman, Editor-in-Chief

For more than a year, gemologists and dealers have suspected so-called natural red andesine was, in reality, colored using copper diffusion. Now research physicist John Emmett has proven these suspicions are quite possible.

Copper diffused andesine wafer, photo courtesy of John Emmett.

Somebody please give John Emmett $5 million for Christmas. It wouldn’t take much prodding to get him to use the money to build and staff the world’s first truly experimental material sciences gem lab. Emmett is convinced such a research facility is the only way the jewelry industry can cut down the scandalous lag time between the introduction of gems sold as all-natural and the discovery that they owe their color to sophisticated processes ceramicists and glass makers use every day to color their wares.

Emmett, who was associate director responsible for laser research and development at the U.S. government’s Lawrence Livermore National Laboratory from 1972 to 1989, now runs a firm called Crystal Chemistry, Brush Prairie, WA, which develops gemstone color and clarity enhancement methods. How fitting that a man charged with keeping America’s weapons systems safe and sound is engaged in gemological civil defense, spending what too often is his own retirement money to discover the ways and means overseas gemstone makeover technicians are turning sows’ ears into silk purses.

Recently, Emmett and his partner Troy Douthit decided to conduct sophisticated experiments to see if widespread suspicions about the artificial nature of the color of TV and Internet andesine were plausible. Sure enough, they were. Here’s how the duo came to their momentous confirmation.

Duplication, Not Detection of Processes

Copper diffused andesine wafer, photo courtesy of John Emmett.

There is a gemological grapevine, and these days it is constantly rustling with rumors. Many of them have to do with suspected treatment of gems that suddenly flood the market and lend themselves to large-scale global marketing via TV and Internet.

As perhaps America’s most respected treater and treatment researcher, Emmett hears as many of these rumors as anyone else. His first instinct as a scientist is to test the validity of these rumors by running tests in his lab. “There is an important step—namely, proving the plausibility of scientific conjecture—that needs to be incorporated into gemology,” Emmett says. “This involves running experiments on the gemstone in question to see if processes alleged to be performed on them can indeed be performed. Once conjecture is proven, then tests can be devised to differentiate natural from treated material.”

Proving conjecture is exactly what Emmett and Douthit did in 2002 when a sudden tsunami of “padparadscha” sapphire hit the market. After gemologists detected the presence of beryllium—a foreign element to corundum—in this sapphire, the team set about proving the possibility of such a treatment in their lab. Their experiments confirmed these suspicions.

Although not noted at the time, the success of Emmett’s experiments with beryllium diffusion expanded the nature of gemology from an exclusively observational science into one equally experimental as well. Emmett and Douthit are not just interested in detection of treatments. As lifelong research scientists, they are interested in proving the possibility of these processes and understanding them, not merely spotting them. That involves replication in a lab. This is where they are unlike most of their peers in the gemological community. Traditional gemology is still mostly observational, a matter of cataloging things seen under a microscope or measured with an array of instruments.

Emmett wants gemologists to question how things happen—their ways and whys—by experimentation. He is convinced that as gemologist become more versed in physical processes, not just materials, they will be able to much more quickly identify new treatments—perhaps even anticipate them. His work on feldspar drives home the importance of this kind of experimentation even more.

From Plush to Cosa Grande

Copper diffused andesine wafer, photo courtesy of John Emmett.

Three years ago, a friend in Bangkok sent Emmett some of the newcomer feldspar and asked him if he thought it was heated. It took him until last March to seriously address that question. By then, the andesine scandals were breaking news. But Emmett felt the trade first had to know if copper diffusion—the chemical process accused of turning yellow stones red—could even be a culprit. “I couldn’t decide, although an eminent gemologist to whom I showed the stones said that if they were corundum he would have been willing to bet they were heated,” Emmett says.

There was great urgency to his experiments. The market was riled because red andesine very similar in looks to Oregon sunstone but from a mysterious, undocumented location was selling at a fraction of the price of West Coast material. Since the Ponderosa Mine in Oregon was the only verified source of natural red, transparent feldspar, doubts were running strong about the newcomer feldspar’s authenticity as all-natural. Many charged it was, in reality, pale yellow material from Mexico that had been diffused with copper to induce red coloration.

True to his creed as a scientist, Emmett took nothing for granted and refused to pre-judge the material based solely on widespread suspicion. Instead he accumulated samples of yellow feldspar from various Oregon deposits, the humongous Cosa Grande mine in Mexico and material represented to the donor (Jewelry Television) as having come from China.

After cutting the samples into 3-4 millimeter thick wafers for testing purposes, he immersed them in a 1% metallic copper chemical compound which he heated to 1200 degrees centigrade for 165 hours in various atmospheres that correspond to difference valence states of copper. Not unexpectedly, results varied. Some stones turned completely red while others exhibited red rinds around the edges as well as other phenomena.

Emmett was now satisfied that some andesine could be colored by what is known as “pipe diffusion.” What’s that? “Feldspar has enormous dislocation planes that act as channels for diffusion mixtures,” he explains. “Given that fact, proving the possibility of diffusion doesn’t come as a too great a surprise.”

Now Emmett wants to turn his attention to recent accusations that green-blue cuprian tourmaline sold as “Paraiba” also owes its color to copper diffusion. Here he has stronger doubts about the plausibility of the charges. “Tourmaline is a much more orderly mineral than feldspar,” he says. “And without those rampant dislocation planes that you find in feldspar to act as conduits, I just don’t see how copper diffusion can be fast enough to work. But I am itching to run a very thorough series of tests before we reach a conclusion one way or the other.”

Are there any donors of material or money to buy material among our readership? Let us know and we’ll pass your offers on to Emmett and Douthit.

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