Latest News

IGI Discovers 6ct. Lab-Grown Diamond Posing as Natural

January 3, 2024  |  Leah Meirovich
IGI fraudulent LGD stone 1280 USED 030124

A 6.01-carat stone that the International Gemological Institute (IGI) recently received for grading turned out to be a synthetic diamond with a laser inscription for a natural one.

The pear-cut lab-grown diamond’s carat weight and physical description were a close match to the online data for a natural diamond graded by the Gemological Institute of America (GIA), whose inscription it bore, the IGI said Tuesday. However, after testing the stone, the lab concluded it was not a natural diamond and, therefore, that someone must have fraudulently paired the natural-diamond report with a synthetic stone.

The institute used photoluminescence spectroscopy to test the diamond, which revealed a doublet caused by silicon-vacancy (SiV) defects, indicating it was created using chemical vapor deposition (CVD). Further review of the stone using microscopy showed a carbon inclusion in place of the feather noted in the GIA report, as well as a cloud, which resulted in a lower clarity grade. IGI also found a slight mismatch in the depth of the stone, but observed those small discrepancies could easily go unnoticed outside of a laboratory, particularly after the stone had been set into a piece of jewelry.

“Everyone in our industry must be vigilant,” said IGI CEO Tehmasp Printer. “As attempted fraud increases, the need for ongoing verification is a necessary step to protect consumers from purchasing misrepresented gems and jewelry.”

The discovery of the fraudulent stone comes on the heels of a number of other industry alerts that lab-grown are being sold as natural, the IGI added.

Italian lab Gem-Tech recently identified three synthetic diamonds bearing GIA inscriptions that appeared to have been forged.

Main image: The lab-grown diamond submitted as natural (left); the fraudulent GIA inscription (right). (International Gemological Institute)

Stay up to date by signing up for our diamond and jewelry industry news and analysis.


IGI fraudulent LGD stone 1280 USED 030124 IGI Discovers 6ct. Lab-Grown Diamond Posing as Natural

Share with others


Clear all search filters