GIA Identifies Surge In Large HPHT-Treated Diamonds

As noted in the December issue of Gems & Gemology’s G&G eBrief, some of the diamonds had flat graphite inclusions with tension “halos” surrounding them. This type of inclusion suggested that the diamond has been processed by HPHT annealing.

“The range of diamonds being subjected to the treatment has also expanded,” said Tom Moses, senior vice president of the GIA Laboratory and Research. “We are confident that we can identify virtually all these treated diamonds as a result of our extensive research in this area, which is one of the most important initiatives at GIA. However, we do not know if this recent surge in treated stones represents a new source or an attempt by some clients to ‘test the systems’ at GIA.”

According to Moses, GIA was contacting the clients both to learn the source of the treated diamonds and to remind them that failure to disclose treatment at all stages of the pipeline is unacceptable.

In addition, GIA said it was reviewing each transaction to determine whether it was appropriate to turn over relevant information to the trade organizations and law enforcement bodies.

“GIA’s mission is to protect the public trust in gems and jewelry,” said Moses. “We take this role very seriously. GIA will not tolerate the intentional failure of its clients to appropriately disclose gemstone treatments.”