NDT breaking the 10 carat barrier: World record faceted and synthetic diamonds investigated

Branko Deljanin (1), Matthias Alessandri (2) , Dr. Adolf Peretti (3) , Mikko Åström (4), Dr. Andrey Katrusha (5)

  1. CGL-GRS Swiss Canadian Gemlab, Vancouver, Canada
  2. GRS Lab (Hong Kong) Limited, Hong Kong, China
  3. GRS Gemresearch Swisslab AG, Lucerne, Switzerland
  4. M&A Gemological Instruments, Järvenpää, Finland
  5. Consultant, St. Petersburg, Russia

Published in GRS Gemresearch Swisslab magazine Contributions to Gemology No. 15, July 2015

Diamonds grown by New Diamond Technology (NDT) in Russia are the largest colorless synthetic diamonds reported to date, with weights up to 60ct crystals and 10.02 ct faceted stones. Using a combination of standard gemological and spectroscopic tests, it is possible to identify all New Diamond Technology (NDT) colorless and blue HPHT-grown diamonds. Synthetic diamonds from NDT can therefore be distinguished from natural diamonds of similar quality.

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