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September/October
2008 |
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Entrance StrategyIt isn't easy to force copper into feldspar. So when gemologist Robert James said copper diffusion was the real cause of red and green in Mexican feldspar sold as natural on TV, and made the official gem of the 2008 Beijing Olympics, no one took him seriously—until he started snapping pictures to prove his point By David Federman, Editor-in-Chief, Colored Stone
Ever read Henrik Ibsen's "An Enemy of the People"? It's a 19th century play about a doctor who discovers that his town's central source of income, its famous health spa, has poisoned waters and must fight an establishment in denial to warn the world at large. For the last few months, gemologist Robert James, president of the International School of Gemology in San Antonio, Texas, has found himself in a situation very similar to that of Ibsen's whistle-blower doctor. He has been charging that tons of feldspar sold on TV and the Internet as all-natural were, in reality, artificially colored by copper diffusion.
And no wonder. A lot was riding on the all-natural status of this feldspar. [Feldspar is a complex gem group divided into two branches: orthoclase and plagioclase. Of interest here is the second group which is arbitrarily divided into six parts, based on the increasing ratio of calcium to sodium: albite, oligoclase, andesine, labradorite, bytownite and anorthite. TV feldspar was sold as both andesine and andesine-labradorite. From this point on, we will refer to the feldspar in question as "andesine," even though some gemologists familiar with this material insist it should be called "labradorite."] First, millions of dollars worth of it were being sold on major shop-at-home TV networks. Second, this andesine had been adopted as the official gem of the 2008 Beijing Olympics. If the color was artificial, the ensuing scandal would be global in scope. Determined to make his case, James disseminated incriminating photographs via the Internet that left those who saw them little choice but to entertain the thought that maybe TV andesine owed its color to some sort of gimmickry after all. In early May, these caught-in-the-act photographs convinced Colored Stone, which had long harbored suspicions of its own about this feldspar, to publish an article sympathetic to James's findings on its Web site. Surprisingly, the magazine received only one letter critical of James' science. The remaining correspondence was overwhelmingly supportive. We encouraged James to continue his research. In June, James decided to write a show-all/tell-all report on TV and Olympic Games andesine that detailed his research methodology and findings. When he offered Colored Stone exclusive first publication rights, we jumped at the opportunity because we felt pretty sure James would supply us with gemological confirmation of our own suspicions. This is when things went wrong—or was it right? You be the judge. From Goof to Grace On July 22, a Web technician accidentally sent the as-yet unedited report to every subscriber on Colored Stone's opt-in email list. After calling James to notify him that his report had been unintentionally released, we published a terse disclaimer the next day, explaining 1) that the report had been released prematurely and 2) that Mr. James' views were not necessarily those of the company. The disclaimer wasn't meant, as some subscribers wrote, to be a retraction. It was straightforward boilerplate meant to admit we goofed. Keep in mind the following: Colored Stone had lobbed a live grenade into the middle of the market it covers, for the report argued and, to us anyway, made a convincing case for what many in the trade already feared: that TV and Internet red and green andesine sold as Asian in origin and all-natural in color was neither. So what was it? The View from Malvern For starters, we had received reliable tips in 2007 that in all likelihood the TV andesine was not as purported, from the Congo or even Tibet and Mongolia. Our sources—including both a geologist who had studied the material and a dealer who had bought large quantities of it—were willing to bet the material was Mexican. Why? First, Mexico was the only known country with a deposit of transparent feldspar capable of supplying enough material for sustained large-scale TV, Internet and Olympics marketing campaigns. Except for Oregon, there was no other known significant source of the kind of material needed for such gargantuan commercial efforts. Second, the very nature of the Mexican material convinced us treatment was required if it was to be sold in red and green varieties. For those not familiar with Mexican feldspar, it is homogeneously yellow—with nary a trace of red or green. If this feldspar was to be sold as red or green andesine, the color would have to be induced. How? This is where things got complicated. Experts versed in treatment who tried to induce red and green in yellow feldspar told us they had failed in their attempts. So while they shared our suspicions, they could not confirm them. But just because they failed didn't mean others hadn't succeeded. Our suspicions were not allayed. Now let's skip to Tucson 2008 where I conducted a seminar on current gemological issues. There renowned treatment expert Ted Themelis told the audience that Thailand's master gem-color processors had developed a means to diffuse heavy elements into gems to induce major improvements in stone appearance. This method was a refinement of the light-element beryllium diffusion method used to convert Madagascar sapphires into "new-find" padparadscha around 2000. True, copper is a transitional element and not "heavy" in the sense Themelis meant. Nevertheless, I felt I had grounds to once again pursue my suspicions about TV andesine. Those doubts only deepened when I learned that no one had ever been able to obtain certified Congolese, Tibetan or Mongolian andesine rough from which the new red and green "all-natural" andesine was being cut. I began to wonder if the "new-find" market mythology that surrounded TV andesine wasn't simply a variation on the new-find mythology used to explain the sudden profusion of fake-color padparadscha a few years earlier. Was the new find simply a new furnace used to artificially color gems? Shortly after my skepticism peaked, Colored Stone's and Robert James' paths crossed. The View from San Antonio
By the time James began openly expressing his doubts about the all-natural status of TV and Olympics andesine, some sellers were admitting that stones were treated—but purely by heating. That didn't make sense. Convinced TV andesine was Mexican in origin, James knew it to be strong in iron and deficient in the coloring agent of copper needed to produce red and green colors. So what good would mere heating do? James set out to find if stones had been altered using a combination of heat and copper diffusion. After collecting more than 100 specimen stones direct from TV and Internet sellers, James raised enough money to purchase a Raman microscope for fine-tuned chemical analyses and spectra. Comparing his specimens to known samples of Mexican material, he found all were, in his words, "virtually identical." Poof! There went the validity of claims that the material was from Africa or Asia. Next, James ran immersion tests of the material—including four stones sold as "Olympic Andesine," the official gemstone of the 2008 Beijing Olympics. All showed green cores and red rims. "What are the chances of this occurring in every andesine I tested?" James asked himself. The most likely way that there could be such consistency of stone interiors, he theorized, was if the red resulted from copper diffusion. James went back to his microscope and examined stones for any tell-tale internal similarities. He found twinning, also called "lamella," but which he nicknamed "ribbons." What, he wanted to know, caused this internal phenomenon? The Shots Seen Round the World "Ribbons" are tiny tubular fissures that run through feldspar, often breaking the surface. If stones were subject to copper diffusion, James felt it only logical that some would show filler material in these cracks. Suspecting that this filler would be most evident in lower-quality stones with numerous filled fissures that had escaped notice by sellers, James went on the Internet and started bidding for inexpensive auction goods.Sure enough, he found filler material crammed into the tiny tubular openings of these "liquidation" stones. His photos of these filler-caked cracks were the centerpiece of the report submitted to Colored Stone in late July and accidentally leaked to email subscribers. To his credit, James sent the report with these dramatic photomicrographs to leading establishment gemologists for their reaction. One of them, Lore Kiefert, head of the American Gem Trade Association's Gem Trade Laboratory, admitted they indicate the presence of some unidentified but suspicious material that she had not previously observed in feldspar. She wants James to submit actual samples of the material he studied to her for further study. Joel Arem, well-known gemologist and author of the highly-praised "Color Encyclopedia of Gemstones," was more unequivocal. In a statement sent to Colored Stone, he wrote as follows: "I have seen the report by Robert James on "Olympic andesine" and other bits of his research data. As long ago as 2003 I had information that led me to believe that the huge volume of red/blue-green "andesine" coming out of China was artificially color-enhanced. I already knew the material was labradorite and not andesine, because I had tested it myself. If the sellers were mislabeling the very species, what other mischief was afoot? I applaud James' thorough approach to this issue and agree with his results. I do still remain open to information proving the existence of small quantities of natural red labradorite from Asia." Other gemologists like Kiefert also hold out hope for a small Asian find of all-natural material which was the source of stones they tested and found kosher. For now, however, the onus of proof that such material has been found in any quantity whatsoever remains on those who sold it—not those who questioned its legitimacy.
In the Aftermath Next, the influential Asian Institute of Gemological Studies posted James' report exactly as it appeared in our dispatch on their Web site. What's more, the Gemmological Association of New Zealand sent a laudatory note to Robert James about his study and asked for permission to reprint it in their quarterly. Suddenly, it seemed as if the gemological world was doing an about-face and accepting the reality of artificially-colored red andesine. That's when former merchandisers of this material started to admit that it was, indeed, treated. Thai Gems, a major Internet seller of red andesine, reclassified the material as colored by "bulk diffusion Fe/Cu." James was being vindicated. What's Next? You can guess which one he has in mind: cuprian elbaite now being sold worldwide as "Paraiba" tourmaline. James is fearful that many African tourmalines have been diffused with copper to legitimize their classification as "Paraiba." His preliminary tests, he says, would seem to confirm his fears. As you can see from the following photographs showing color cores and rims eerily similar to those found in copper-diffused andesine, Asia's alchemists may be working the same kind of false wonders with tourmaline that they have with feldspar.
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