top of page

6-carat Stone With Fake Inscription Submitted To IGI

By Julia Griffith

A 6-carat laboratory-grown diamond, falsely presented as a natural diamond with a GIA inscription, was presented to the International Gemological Institute (IGI) in Tel Aviv. IGI promptly identified its actual origin. Let's delve into the specifics...

Pear shaped laboratory-grown diamond © IGI

The focal point is a 6.01ct pear-shaped laboratory-grown diamond, created through CVD synthesis—a method commonly employed for larger laboratory-grown diamonds. This stone mimics the characteristics outlined in a falsely linked diamond report from the Gemological Institute of America (GIA), closely matching size, shape, and quality (G colour).

The most noticeable distinctions between the imitated stone and the GIA report are subtle. IGI noted a difference in depth measurement and a slightly lower clarity grade on the laboratory-grown diamond.

Screening tests and photoluminescence (PL) spectroscopy revealed its synthetic origins.

Fake laser inscription © IGI Tel Aviv


To protect themselves against such stones and other undisclosed laboratory-grown diamonds, numerous companies have made investments in education and diamond verification equipment to conduct initial assessments in-house.

Organisations like the London Diamond Bourse permit their members to utilize various diamond verification tools on-site, with no cost to Bourse Members. A similar service has been introduced by the Diamond Manufacturers and Importers Association (DMIA) in New York. Additionally, the GIA has initiated a program this week that provides a complimentary same-day testing service at their New York laboratory specifically for validating stones bearing a GIA inscription.

Owing to these challenges, several grading laboratories have experienced an increase in the number of stones being submitted for an updated report to verify the authenticity of diamonds.

The diamond report the 6-carat laboratory-grown diamond was falsely linked to © GIA


IGI has encountered previous instances of sizable laboratory-grown diamonds with deceptive inscriptions. In June 2021, a 6.18ct round brilliant stone was received by the lab, referencing a GIA report claiming a D/Flawless grade. This is the largest stone identified in connection with this reported trend of fraud thus far.


The photoluminescence spectrum of the 6.01ct laboratory-grown diamond. The 737nm peak indicates a silicon vacancy - an absorption feature present in CVD laboratory-grown diamonds © IGI Tel Aviv


Unfortunate possibility

We are likely in the early stages of witnessing the surge in such deceptive practices. As the price disparity between natural diamonds and laboratory-grown diamonds widens, the likelihood of these incidents occurring also increases.

With the ongoing decline in the prices of laboratory-grown diamonds, the allure of attempting such deceit grows, driven by the diminishing financial risk associated with the fraudulent scheme.

A comparable 6-carat stone (6-carat G/VS2, EX EX) currently has a wholesale price as low as a couple of thousand dollars. Considering that its natural diamond equivalent wholesales at least 60 times that price, the imbalance between the financial risk and potential gain from such activities is evident.

If these stones drop further in price, the frequency of such incidents could become even more widespread. Consider the possibility of numerous lower-value, smaller laboratory-grown diamonds that have already been fraudulently inscribed, with the intent to profit by deceiving others.

Vigilance is crucial. Unfortunately, I am inclined to believe that this marks the genuine beginning of the impact of laboratory-grown diamonds on our cherished industry.

Key takeaway: Test everything.


138 views0 comments

Recent Posts

See All


Thank you for subscribing!

SUBSCRIBE HERE  to join our monthly newsletter:

bottom of page