HRD Antwerp has added a report to its website about its discovery of (near-) colorless lab-grown diamonds featuring octahedral and other “natural” shapes.
The lab said that whereas previously it was fairly straightforward to distinguish natural rough diamonds from lab-grown rough diamonds due to the cubo-octahedral shape seen with diamonds produced by HPHT (High Pressure High Temperature) and the characteristic plate structure of diamonds produced by CVD (Chemical Vapour Deposition), it is becoming more difficult as rough lab-grown stones featuring “a morphology previously unique to natural diamonds” are entering the market.
The more natural shapes were seen in rough melee goods produced by Chinese company Taidiam, which creates both HPHT and CVD lab-grown diamonds. The goods varied in size from 0.01 carat to 0.04 carat.
“A more in-depth investigation on a microscopic level, however, still reveals the remnants of a seed crystal used to position the precipitated carbon atoms, and / or other characteristics inherent to lab grown diamonds,” said Dr Katrien De Corte, chief education officer HRD Antwerp.
“An infrared spectroscopy analyses by our research team has also demonstrated that all colorless diamonds included in the examination were found to be type IIa or type IIb.”