The 6.87-carat lab-created diamond was submitted to the GIA for testing. According to a report in Gems & Gemology, the near-colourless stone was created using the chemical vapour deposition (CVD) method to closely resemble a natural octahedron.
Advanced laser testing using Raman spectroscopy confirmed the diamond was synthetic. This is the first reported case of a CVD diamond intentionally cut to imitate a natural rough diamond, and the authors suggest it has no practical purpose beyond deception.
“There is currently no evidence of any widespread switching of synthetic for natural diamonds in the rough diamond pipeline, but overreliance on practices such as assessing the ‘heft’ of a stone would obviously not allow reliable screening for synthetic diamonds,” the report explains.
“Should synthetic diamonds fashioned in this way become more prevalent, an immediate screening solution for rough diamonds could be implemented through adaptation of existing screening instruments for polished diamonds.
"Analysis of this stone with a wide range of diamond verification instruments gave the correct referral results, and the main characteristics were consistent with those seen routinely in polished synthetic diamonds."
It was explained that shaping a CVD diamond in this manner is challenging and inefficient, resulting in significant material loss. Only one pair of the diamond’s opposite faces was parallel, and none matched the crystal planes typical of natural diamonds.
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