CIBJO: 4Cs for Natural Diamonds Only, Lab Growns are "Synthetics"

(IDEX Online) - Only natural diamonds should be graded with the 4Cs, says CIBJO (the World Jewellery Confederation).

And the word "synthetic" should be regarded as the preferred term to describe diamonds created through industrial processes.

CIBJO, the body that represents the gem and jewelry industries globally from mine to marketplace, aims to reinforce the distinction between lab grown and natural stones.

It has published a report on 4Cs grading and preferred diamond descriptors ahead of its annual congress in Italy in September.

Udi Sheintal (pictured), who heads CIBJO's Diamond Commission, said: "When the 4Cs grading scale is used by the synthetic diamond industry to describe its production, the consumer is misled to believe that synthetic diamonds are rare like natural diamonds."

He said that was clearly not the case, because the synthetic diamond manufacturer determines and controls the production parameters, to achieve predetermined quality characteristics.

He also said that times had changed since CIBJO decided in 2010 that the terms "laboratory-grown" diamond and "laboratory-created" diamond were acceptable ways to describe manufactured diamonds.

At the time, the decision appeared both reasonable and constructive, he said, but it was now appropriate to revisit that decision.

"Existing terminology may no longer serve consumers as effectively as originally intended," he said.

GIA ditched 4Cs grading for lab growns last October, in favor of a simple distinction between premium and standard stones.

In May of this year, the African Diamond Producers Association (ADPA) called for lab growns to be measured in grams rather than carats, and for 4Cs grading to be reserved only for natural stones.