The International Gemological Institute’s (IGI) Hong Kong laboratory has certified the largest chemical vapor deposition (CVD) laboratory-grown diamond received to date.

With a finished weight of 12.75 carats, this collection-quality man-made gemstone was fashioned from a 46.20 carat CVD-grown rough crystal.

According to its creator, Shanghai Zhengshi Technology, it is the largest CVD lab-grown diamond ever produced.

Advertisement

“For the past 15 years, IGI has been at the forefront of lab-grown certification and education,” stated IGI CEO, Roland Lorie. “With this milestone, the Institute continues to establish itself as the prominent leader in the industry and opens the door for future opportunities to exceed current gemological standards.”

IGI gemologists confirmed the 12.75ct stone was Type IIa, giving it exceptional chemical purity and transparency, with VVS2 clarity, F color, and triple-excellent marks in cut-quality and finish.

Following detailed scientific analysis, the laboratory substantiated that the stone had not undergone any post-growth treatments, so it can be categorised as a pure CVD diamond.

“A laboratory-grown diamond of this carat weight, with such a high clarity and color grade, is a remarkable achievement in CVD cultivated diamond technology,” said IGI Hong Kong managing director, Bob Van Es. “As the industry leader in the certification of laboratory-grown diamonds, IGI will continue to follow these new developments closely.”

This news comes only three months after the IGI analysed the Guinness World Record-holding biggest black lab-grown diamond.