RAPAPORT… The International Gemological Institute’s (IGI) Hong Kong laboratory has graded a 12.75-carat synthetic diamond, the largest chemical vapor deposition (CVD) stone it has ever received.
The lab-grown stone, cut from a 46.20-carat rough, has F color and VVS2 clarity, and is type IIa, the IGI said Monday. It was created by Shanghai Zhengshi Technology Co., which claims it is the largest lab-grown diamond ever produced.
“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,” noted IGI Hong Kong managing director Bob Van Es.
Last month, IGI reported it had graded a 115.65-carat, black synthetic diamond created using High Pressure-High Temperature (HPHT). That stone ranked as the largest lab-grown diamond of its color, IGI added.
Image: The 12.75-carat CVD diamond. (International Gemological Institute)
Lab Grades Its Largest CVD Diamond
The Bottom Line
- IGI Hong Kong lab graded a 12.75-carat synthetic diamond, the largest CVD stone it has processed.
- The diamond, cut from a 46.20-carat rough, is F color, VVS2 clarity, and type IIa.
- Shanghai Zhengshi Technology claims this is the largest lab-grown diamond ever produced using CVD technology.
Summary by Rapaport AI
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