Lab-grown diamonds passed off as natural, and gemological institutes are ceasing to classify them.
A few days ago, Gemological Science International discovered lab-grown diamonds mounted in jewelry with natural brown diamonds. The problem is that the synthetic diamonds had not been declared. To uncover the fraud, the GSI conducted a thorough screening process using advanced technologies, including Fourier Transform Infrared Spectroscopy, DiamondView imaging, and liquid nitrogen-cooled Raman spectroscopy. In short, tools only large testing laboratories have at their disposal. Gemological Science International discovered that the lab-grown stones ranged from nearly colorless with faint brown modifiers to an elegant dark brown. This news adds to the growing number of similar frauds and is alarming the jewelry industry.
The problem of synthetic diamonds passed off as natural stones (which are more expensive) is compounded by the decision by major gemological institutions to distance themselves. Starting in January 2026, for example, HRD Antwerp will no longer certify loose lab-grown diamonds. “The decision stems from the laboratory’s desire to focus its services on natural diamonds and finished jewelry, maintaining the excellence that has always distinguished its certifications,” a statement reads. HRD Antwerp, however, will continue to classify jewelry containing lab-grown diamonds. The decision marks a significant shift in the certification landscape, but the goal remains to ensure transparency, trust, and consumer protection, the Belgian company explains.
The Italian Gemological Institute was also the first to decide not to certify synthetic diamonds. Months ago, the world’s leading institution, the Gemological Institute of America, also announced it would abandon the classification for lab-grown diamonds, which is the same as that for natural diamonds, after introducing an evaluation according to the classic 4Cs used for natural stones in 2020. The new grading standards are currently unclear. But the goal is certainly to highlight the stark difference between gems formed millions of years ago and those just weeks old, created by a sophisticated machine in China or India.
Although gemologists and many jewelry companies are wary of factory-grown diamonds, the synthetic gemstone market is expanding. In 2024, the global synthetic diamond market was valued at $25.9 billion according to Global Market Insights, thanks to their significantly lower cost, which is particularly attractive to younger generations. Thanks to marketing, lab-grown diamonds also enjoy a reputation as more environmentally sustainable stones, even though they require a large amount of energy to create.
