Does GIA’s Turnabout on Lab-Grown Diamonds Matter?

By Rob Bates | June 04, 2025

GIA’s new system for grading lab-grown diamonds has been met with a predictably divided response: kudos from natural diamond partisans, and anger in the lab-grown community, who complained the traditional trade was once again denigrating their product. (Though some growers have arguably done a fine job of that themselves.)

Earlier this week, GIA announced it was changing how it grades lab-growns, abandoning the 4Cs scale—which it’s used on LGDs for the past five years—and instead rating them simply as either “premium” or “standard.” (The worst-looking stones won’t get grades.) It’s the third time GIA has overhauled its lab-grown grading policy.

For all the commotion over the change, we’re talking about a service that not many people use. GIA president and CEO Susan Jacques has said that fewer than 5% of the lab-grown stones on the market end up at GIA.

But back in mid-2020, when GIA bowed to pressure and agreed to offer full 4Cs grading for lab-growns, it was big news. That move gave the lab-grown industry clear bragging rights—it could now say, “GIA grades LGDs the same as naturals.”

Yet GIA was responding to a market need. At the time, high-end lab-growns were selling for upward of $20,000. Anyone who bought a stone that expensive would likely want a GIA report.

We don’t see those prices much anymore. Right now, most growers just want their reports to be as cheap as possible. Sellers say standard grading reports sometimes cost more than the stones.

GIA has explained the new policy by noting that 95% of lab diamonds now fall into a narrow range of color and clarity, so the traditional scale is no longer appropriate. Its revamped reports will likely be less expensive than what it currently offers, which could make them more attractive to growers.

However, the created gem business seems stuck on the 4Cs because that’s what consumers know. And strictly on a cost basis, it might be hard to compete with services that allow “in-factory” grading or that sell “quality control” reports for five bucks.

GIA’s decision might best be seen as a reflection of the current market. When lab-grown was white-hot, GIA climbed on board. Now that the LGD market has cooled (somewhat), it’s hopping off.

Ultimately, this is the kind of issue that seems to interest the trade more than consumers. Is it a victory for the natural side? Probably. Will it affect sales in any way? Probably not. I’ve been watching the lab-grown–versus–natural “war” for a long time. It’s produced far more losers than winners.

(Photo courtesy of GIA)