RAPAPORT... Recent advances in growing and treating diamonds has garnered much public attention, yet relatively little has been published on the subject. AG&J has witnessed large and small companies pursing investments in HPHT / APHT / LPHT treatments, irradiation and especially technology for growing HPHT and CVD synthetic diamonds. Many companies are already in place and ready to capitalize on these new techniques and it is only the complexity and the sophistication of the technology that slows new investment. This text will deal with the problem of identification and certification of diamonds when synthetic diamonds, larger than 2 carat, become common enough to sufficiently meet the needs of the market. We will address the potential risks certifying laboratories run in loosing consumer confidence, as well as the ultimate question; how can consumers and jewelers trust that mounted diamonds have been identified and certified? Based on the data contained within almost all diamond certificates, it is relatively easy -- especially with round diamonds -- to manufacture identical replicas of certified diamonds. These replica diamonds can be made from either HPHT treated or synthetic diamonds. The fraudulent replica will then replaces the original diamond and will be sold with its authentic certificate. This process is done primarily with type IIa and IIb diamonds, with a high color -- H+ and primarily with high-clarity, VVS +. This problem was predicted and spotted many years ago. Replicas were made using type IIa, HPHT treated diamonds, but the process has evolved to include irradiation and heating as a “post treatments.” These new processes increase the likelihood that laboratories will be forced to bear the responsibility for this fraud. For example, in the case that a replica diamond with a certificate is sent to a laboratory and is issued a new certification (describing the diamond as treated or undetermined -- Gemological Institute of America comments: Whether the color of this diamond is of natural origin or result of an artificial process cannot currently be determined) the fault will inevitably fall on the shoulders of the original certifying lab. This is one way in which these replicas threaten the integrity of our industry. The exact number of cases in which this has occurred is difficult to know, but is most likely limited because replicas are made from natural type IIa diamonds. Until today these cases were only rumored in closed professional circles, and estimates of the number of replicas vary greatly. Surely, though, the answer to this question resides within the gem labs databases. With an ever-increasing supply of synthetic diamonds hitting the market, it is not difficult to conclude that synthetic diamonds will be used as fraudulent replicas for certified diamonds. The problem is particularly serious in mounted diamonds and jewelry. AG&J has offered technical solutions for the screening and identification of mounted diamonds to many large jewelry manufacturers, but within the market, this very real threat to diamond confidence is not yet recognized as a problem worth addressing. Unfortunately, the most effective solution to this problem is both complicated and expensive. We call it “Diamond Fingerprinting.” It includes detailed spectroscopy/imaging in all areas. Unfortunately, this process is prohibitively expensive for most labs and requires a large investment of both time and money. AG&J proposes the following solution, which applies to both mounted and un-mounted diamonds: All diamond certificates should be expanded to include two graphs -- IR absorption and 365 or 405 induced bulk photoluminescence, with the added obligation of storing these graphs in a database. FTIR instruments are already well known to the industry and owned by most laboratories; 365 Luminescence is a simple, inexpensive system and is described as an "express-spectrometer" in our literature (page 6 of Simic / Zaitsev, "Characterization of diamonds color-enhanced by Suncrest Diamonds USA"). These two procedures could then be standardized into one simple system. Since mounted diamonds require different adjustments and customized instruments, new tools to accomplish this procedure would be the only new investment required. In our opinion, the essential principle of using at least two methods of identification would then be satisfied. Also, the implementation of these methods would be relatively easy and inexpensive for small and large laboratories alike. Both methods have no limitations in size, color or shape of diamond. Based our experience, the combination of these two methods could easily determine the authenticity of more than 95 percent of all diamonds inspected. About AG&J
Analytical Gemology and Jewelry is a gemological laboratory located in New York’s Diamond District, specializing in the identification of diamonds and their treatments. The laboratory is equipped with state-of-the-art equipment, including a Renishaw Raman with multiple lasers, and applies proprietary procedures for sophisticated gemological analysis. For more information, visit their website at www.agandj.com
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