No more 4C grading, now lab-grown diamonds are ‘premium’ or ‘standard’

MUMBAI: In a move poised to reshape the global gem trade, the Gemological Institute of America (GIA) has announced it will no longer apply the 4Cs grading system-cut, colour, clarity, and carat weight-to laboratory-grown diamonds.

Instead, beginning from later this year, GIA will issue simplified descriptors for such stones-broadly classifying them as ‘premium’ or ‘standard’- or no grade altogether if the quality is lacking.Industry experts said this formally reinforces that lab-grown diamonds (LGDs), while chemically similar, are materially and symbolically distinct from natural diamonds, and must be evaluated on separate terms.

“This is a crucial evolution in diamond classification,” said Kirit Bhansali, chairman of the Gem & Jewellery Export Promotion Council. “By replacing the 4Cs with new descriptors for lab-grown diamonds, GIA removes ambiguity and ensures consumers clearly understand the differences. For India-home to a thriving ecosystem of both natural and lab-grown diamond manufacturing-this distinction will bring balance and transparency, bolstering trust across the value chain.”

Ashok Gajera, managing director of Laxmi Diamonds, said the move to not grade the diamonds following conventional norms comes amid increasing industry introspection on how lab-grown diamonds are positioned and priced. Unlike natural diamonds, which form over billions of years deep within the Earth, LGDs are created in laboratories within weeks-raising persistent debates about their long-term value and desirability.

De Beers India’s managing director Amit Pratihari welcomed GIA’s announcement, noting that “it reaffirms the emotional and geological uniqueness of natural diamonds”. But Mukesh Patel, owner of Greenlab Diamonds, a lab-grown diamond manufacturer, said there were multiple other agencies that grade lab-grown stones, and a very small share of lab-grown diamonds were graded by the GIA. Henry Smith, head of sales at the Institute of Diamonds (part of the De Beers Group), called GIA’s decision a “scientifically sound” update.

“Natural diamonds and synthetics differ in trace elements, growth patterns, and formation timelines. Treating them with the same grading lens can lead to misinterpretation. This shift acknowledges those differences and safeguards the gemological integrity of the industry.”