In a statement released on 6 February, GSI stated that a range of lab-created diamonds mounted in jewellery had been discovered during screen processes.
In some instances, the lab-created diamonds are cut to imitate natural diamonds with fractures, and pinpoint clouds detected that may lead to the diamonds passing standard observation.
President Debbie Azar said the importance of using proper processes, equipment and expertise when identifying diamonds was highlighted by these discoveries.
"Over the past several months, our team has seen a rise in laboratory-grown coloured diamonds, primarily in brown, yellow, and pink, being mixed in with natural-coloured diamonds in jewellery," she said.
“The challenge arises as most jewellery screening equipment in the market is designed to screen white near-colourless diamonds.”
GSI was established in New York City in 2005 and offers gemstone identification and grading services on four continents.
In January, authorities in Hong Kong arrested four people concerning a large-scale money-laundering scheme that involved the misrepresentation of lab-created diamonds.
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