GSI Cautions Trade: Surge in Undisclosed Colored Laboratory Grown Diamonds

Surge in Undisclosed Colored Laboratory Grown Diamonds

February, 2024 (New York, NY): Gemological Science International (GSI), a global leader in diamond and jewelry certification, has raised a red flag over a notable increase in undisclosed laboratory-grown brown, yellow, and pink diamonds infiltrating natural diamond jewelry and posing as natural diamonds.

“Over the past several months, our team has seen a rise in laboratory-grown colored diamonds, primarily in brown, yellow, and pink , being mixed in with natural-colored diamonds in jewelry,” says Debbie Azar, President, and Co-Founder of GSI.

“The challenge arises as most jewelry screening equipment in the market is designed to screen white near-colorless diamonds” , Azar adds.

GSI utilizes a proprietary process for screening and detection of finished diamond jewelry. This process includes distinctive knowledge and expertise, advanced equipment and most recently AI enabled equipment all of which enabled us to detect these undisclosed laboratory grown colored diamonds.

Many of the undisclosed laboratory grown colored diamonds detected by GSI were Type IIA   with a single nitrogen. All were mounted in jewelry and vary in size, ranging from melee and as large as 1ct.

In some instances, the undisclosed lab-grown colored diamonds were intentionally cut to mimic natural diamonds. Severe fractures, pinpoint clouds, and polished-over “naturals” were observed, including distinct brown grain lines. These features closely resemble those found in natural diamonds, potentially passing standard gemological observation.

GSI continues to stress the importance of using proper processes, equipment and expertise when identifying diamonds.

The advancing technology in diamond growth is contributing to increased success by growers to replicate natural diamonds more and more. GSI remains a global leader in testing and detecting undisclosed lab-grown diamonds in finished jewelry, ensuring the integrity of the industry. Currently, GSI is the only major laboratory that offers screening and detection for finished diamond jewelry globally and at scale- screening millions of diamonds each year.


Gemological Science International (GSI) is the only major gemological organization established in the 21st century. Founded in 2005 in New York City, it has grown to become one of the largest gemological entities in the world with laboratory facilities spanning four continents. Utilizing cutting-edge processes and proprietary technologies, along with a commitment to the highest ethical standards and practices, GSI provides manufacturers and retailers globally with a wide range of gemstone identification and grading services. The company is committed to advancing gemological research and offers gemological educational programs for trade professionals and the general public.

Disclaimer: This information has been collected through secondary research and TJM Media Pvt Ltd. is not responsible for any errors in the same.