GIA Spots Treatment Fraud with 6ct. Diamond

RAPAPORT... The Gemological Institute of America (GIA) has uncovered atreated diamond carrying a false inscription that fraudsters had apparentlycreated to make the stone appear untreated. Swindlers appear to have carefully selected a grading reportfor an untreated diamond with extremely similar characteristics to theirtreated stone, and created a fake GIA laser imprint on the treated stone'sgirdle, according to a grader's lab note. The organization's Hong Kong laboratory received the roundbrilliant, 6.30-carat, F-color, internally flawless natural diamond forverification of its grade, Billie Law, who works at the GIA in Hong Kong, wrotein the spring 2018 issue of the institute's journal, Gems & Gemology. Scientists found the polished stone's characteristics wereinconsistent with a report the GIA had issued a few months earlier for adiamond with an identical code on its girdle. That number referred to afractionally smaller diamond - 6.30216 carats, in contrast with the6.30402-carat stone in front of them - with F color but VVS1 clarity. The other difference was that the stone the gemologists hadin their hands was clearly treated using High Pressure-High Temperature (HPHT),a common method for improving a diamond's color. The scientists checked thisusing spectroscopic testing that easily revealed the stone's true nature, Lawwrote. "This case should raise awareness among the industry and thepublic that, although rarely encountered in larger stones, this kind of frauddoes exist," the grader continued. "Verification services at GIA confirm thatan item is exactly the same as the one described on a previous report and hasnot been recut or treated - or, as in this case, replaced with asimilar-looking stone." Grading laboratories have discovered several such cases inrecent years, though usually involving smaller stones. In 2017, the GIAidentified a girdle inscription on a 1.76-carat synthetic diamond to be aforgery created by fraudsters trying to pass it off as a natural stone. Lastmonth, China's National Gemstone Testing Center said it had received a 3.10-caratsynthetic-diamond ring carrying a fake report and inscription that falselypresented it as natural.Images: Tony Leung and Billie Law