Identification of HPHT-Treated Yellow to Green Diamonds
Greenish yellow to yellowish green HPHT-treated diamonds exhibited highly saturated body colour, well-defined brown to yellow octahedral graining and visual evidence of heating, among other characteristics.
Diamond with High Concentration of Nickel
Analysis of Fancy Light greenish yellow diamond leads to detection of nickel, as well as an inclusion that gives a colour-change effect.
The “Type” Classification System of Diamonds and Its Importance in Gemmology
Knowledge of type allows gemmologists to better evaluate if a diamond might be treated or synthetic, and whether it should be sent to a laboratory for testing.
Spring 2015 G&G Examines Blue Spinel, Chinese Jewellery Design and the Latest in Synthetics
G&G Brief presents an overview of the content of the Spring 2015 issue of Gems & Gemology.
Gems & Gemology’s 7 Most Unusual Encounters from 2019
Check out some of the most interesting and unusual diamonds and coloured stones submitted to GIA’s laboratories in 2019.