The GIA (Gemological Institute of America) laboratory in Hong Kong recently evaluated the largest chemical vapor deposition (CVD) laboratory-grown diamond seen by the Institute. Produced by Ethereal Green Diamond in India, the 34.59 ct, 24.94 × 13.95 × 9.39 mm, emerald-cut laboratory-grown diamond was evaluated as VS2, G color. The size of the largest CVD diamond seen by GIA increased by 111% since the Institute reported on a then record-sized 16.41 ct CVD laboratory-grown diamond in 2022.
Gems & Gemology (G&G), GIA’s quarterly professional journal, recently published an online research note that includes all observations and spectroscopic features of this latest record CVD-grown diamond. The research note will appear in the Summer 2023 print edition of the journal.
“This more than two-fold increase in size within one year is an impressive technical achievement in CVD diamond growth,” said Tom Moses, GIA executive vice president and chief laboratory and research officer. “With such production improvements, correct identification and disclosure are critical to maintaining consumer trust; this is another example of why GIA devotes significant resources and research to protect consumer confidence.”
This 34.59 ct CVD laboratory-grown diamond has minute features that resulted in it being evaluated as VS2 for clarity. Researchers found small black graphite inclusions, some along the inside of the body, while others formed clusters of clouds between growth layers. Microscopic observation showed a weak “oily” or wavy graining looking through the table, a feature sometimes seen in CVD laboratory-grown diamonds.
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