The Fall issue of Gems & Gemology published by the Gemological Institute of America (GIA) contains an article -  “Observations on CVD-Grown Synthetic Diamonds: A Review” – presenting the  collated statistical data and distinctive features    emerging  from  the study   of  several hundred faceted CVD-grown synthetic diamonds by  GIA researchers.  The material contained in the article  was collected by GIA researches through studies  from the year 2003 through to June 2016.

“This study, the first comprehensive summary published on such a large number of gem-quality CVD synthetics, describes the reliable means of identifying them, with a focus on material currently marketed for jewellery use,” G&G said in an abstract of the piece.

The article said that most CVD synthetic diamonds analysed by the GIA have been in the near-colourless or pink colour ranges, with clarity grades comparable to those of their natural counterparts. “Faceted CVD samples are generally 2 ct or less, though the sizes are increasing,” G&G warned. “They can be identified by their distinctive fluorescence pattern using the DiamondView imaging instrument, and by the detection of the silicon-vacancy defect using photoluminescence (PL) spectroscopy. Some visual gemmological characteristics provide indicators, but not definitive proof, of CVD origin.”