If the interest demonstrated at the "Screening & Identification of Synthetic Diamonds" seminar hosted by GIA at last week's India International Jewellery Show is any indication, undisclosed mixing of synthetic and natural diamonds is of great concern in India. The Tribune India writes, "According to industry sources, many small traders are quietly mixing the lab-cultured stones with natural diamonds and palming the consignment off to unsuspecting buyers. 'There is a sudden increase in this malpractice because of the slump in the diamond business,' says Ashok Zaveri, a diamond jeweler from Opera House in South Central Mumbai." Worse still, say industry veterans, the mixed consigments are finding their way to international buyers. Since synthetic diamonds are much cheaper than natural stones, traders who mistakenly buy them end up with big losses. “The illegal practice of mixing synthetic diamonds with natural diamonds is hurting the credibility of Indian exporters,” said Sanjay Kothari, former chairman, Gem and Jewellery Export Promotion Council (GJEPC).
Mathew Hall, Director of the GIA laboratory in India, told The Diamond Loupe last week about the ongoing game of cat-and-mouse being played between synthetic diamond growers and the grading labs. "They pay close attention to our technologies," said Hall. "They know what we are looking for, and try to eliminate those indicators. The more sophisticated our tools become, the more sophisticated their techniques will become." He said that GIA anticipates synthetic diamond production will continue to increase and emphasized the need for automated screening. "There are approximately 10,000 HPHT pressses in China. One press can produce approximately 50 carats of 2 mm in size in 12 hours, so you do the math." Again, however, the real issue is the unscrupulous practices of those that try to trick unsuspecting buyers by mixing their parcels of stones.