Editor’s Note
This article discusses the prevalence of treatments in the lab-grown diamond industry and the ongoing debate about whether such processes should be disclosed to consumers. The text has been updated to reflect reader feedback questioning the phrase “overwhelming majority.”
It’s no secret that an overwhelming majority of lab-grown diamonds are treated by either electron irradiation or high-pressure, high-temperature (HPHT). (UPDATE: Some commenters disagree with the phrase “overwhelming majority.”)
Sara Yood, senior counsel for the Jewelers Vigilance Committee (JVC), says that, by law, growers must note radiation treatments, as irradiated diamonds and gemstones are subject to oversight by the Nuclear Regulatory Commission (NRC).
Ben Hakman, founder of Diamond DNA and a lab diamond consultant, says treatments can leave a brownish and sometimes brown-pinkish tinge, and “as grown” diamonds fetch a premium.
But Angelo Palmieri, president of the New York City–based grading lab GCAL, says he’s “not convinced there’s a value differential in the market…. It’s just not an issue that comes up.” He says that even some diamonds labeled “as grown” are treated during the production process.
Of course, there’s another issue here: It can be harder to spot a treatment in a lab-grown than a natural—and the treatments on lab-growns are easier to disguise, says Palmieri.
An Australian company, Gemetrix, has just introduced a lab-grown detector that founder John Chapman feels can spot treatments on any kind of stone.
Gemological Institute of America (GIA) spokesperson Stephen Morisseau says that the GIA is “confident” it can “detect HPHT treatments to improve or alter the color of natural and both CVD and HPHT laboratory-grown diamonds.” He adds that while GIA “believes and has consistently held that any gemstone treatment must be disclosed,” it, too, doesn’t include treatment info on its synthetic reports “for now.”
In mid-2017, I wrote a piece about a lab diamond seller, Jason Payne of Ada Diamonds, who complained that two companies sold him parcels with “undisclosed” naturals. A lot of people laughed at this. I asked if he was “trolling the trade.” But in retrospect, he had a point. Some consumers clearly prefer man-made gems. They shouldn’t buy mined diamonds believing they are lab-grown, and vice versa.
Legally, companies don’t have to modify the word diamond, as the word is generally assumed to mean a natural product. But if a consumer thinks they are buying created gems and they are buying something else, that’s a problem, Yood says.
Payne, for his part, screens all his parcels, just like natural companies now have to screen theirs.
Under the Patriot Act, dealers who sell more than $50,000 in precious stones, gems, and jewelry are required to maintain an anti–money laundering (AML) program.