CIBJO Mulls Whether to Call Lab-Grown Diamonds “Synthetic”

By Rob Bates | October 31, 2025

CIBJO, the World Jewellery Confederation, says it’s reexamining the question of what to call lab-grown diamonds, but contrary to some reports, it hasn’t made any decisions on the matter yet.

Last month, in a special report published on CIBJO’s website, Udi Sheintal, head of the organization’s diamond commission, argued that CIBJO’s Diamond Blue Book should no longer endorse the term laboratory-grown for non-natural stones and that they should instead be called synthetic. The Diamond Blue Book currently approves both terms.

At the CIBJO Congress in Paris this week, the event’s host, Bernadette Pinet-Cuoq, executive president of French jewelry association UFBJOP, endorsed that change.

“It is essential to question the acceptability of the word laboratory, and to reestablish a clear boundary between natural diamonds and synthetic ones,” she said.

Despite all this, CIBJO president Gaetano Cavalieri tells JCK the group has not agreed on what it will do, and there’s a long, deliberative process ahead.

“We haven’t decided to go back to synthetic,” he says. “It is up to the diamond commission to put this on the agenda. Most likely, we will put it on the agenda.

“But the decision process at CIBJO is not easy. It’s very complicated. It has to pass through committees, and then it has to be passed on another committee, and then it goes to the commission, and to the sector, and then to the board of directors.”

This process could take a year or longer, says Cavalieri.

“We will do our homework, so we make the right decision,” he says. “I don’t know what it will be.… The market is asking that industry authorities consider [the issue]. So we’re considering it.”

Lab-grown sellers will almost certainly oppose the requested change, as they have long considered the term synthetic pejorative. Cavalieri says CIBJO will take all opinions into account.

“Everyone is welcome to speak up,” he says. “We are open. We never say one part of the industry is good, the other part is bad. We have someone from the lab-grown community on our lab-grown committee.”

While Cavalieri didn’t endorse the change, he seems at least sympathetic to it.

“CIBJO’s main mission is consumer confidence,” he says. “[Using the word synthetic] does not mean that one is real and the other is fake. It simply means they are two different products.

“The bottom line is that [lab-grown] prices have fallen. And when the prices fall, the people who bought the piece at $1,000 and then see the same product is $100 may feel that it is not a good choice.”

In 2018, the Federal Trade Commission (FTC) removed synthetic from its list of recommended descriptors for technologically produced gems.

“The record indicates consumers mistakenly believe synthetic means an artificial product such as cubic zirconia, which lacks a diamond’s optical, physical, and chemical properties,” the FTC wrote.

Since the agency didn’t prohibit use of the term—despite requests from growers to do so—it’s not clear what practical effect the ruling had, as very few sellers use synthetic and the agency had already okayed lab-grown and lab-created.

Even so, the decision remains controversial among natural diamond advocates, and some are now trying to bring synthetic back.

In a few cases, they’ve had success. In 2023, French authorities, amid lobbying from UFBJOP, declined to change a two-decade-old ruling that said synthetic was the only appropriate descriptor for lab-grown products. That same year, a royal decree in Belgium stated that synthetic diamonds should be sold by the gram and not measured in carats, like natural diamonds.

Although CIBJO decisions don’t have the force of law, many governments are guided by the Blue Book when they develop policy, Cavalieri notes.

“What we say may affect the markets and the industry,” he says. “Whatever decision we take, including the decision to maintain what we have today, we have to have a very good reason for doing it, and we have to explain why we did it.”

Top: Gaetano Cavalieri and Bernadette Pinet-Cuoq at the CIBJO Congress (photo courtesy of CIBJO)