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Check out some of the most interesting and unusual diamonds and coloured stones submitted to GIA’s laboratories in 2019.
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The Argyle diamond mine is the only known source of type IaB hydrogen- and nitrogen-rich diamonds coloured grey to blue to violet.
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G&G Brief presents an overview of the content of the Spring 2015 issue of Gems & Gemology.
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Pink CVD lab-grown products can be separated from natural and treated-colour natural pink diamonds by a combination of gemmological and spectroscopic properties, which are explored in this study.
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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.
Read MoreGreenish 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.
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This article, from the Autumn 2009 issue of Gems & Gemology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemology.
Read MoreThe Diamond Trading Company (DTC) Research Centre had the opportunity to examine a diamond that, on submission to a commercial gem laboratory, turned out to be a coated pink diamond.
Read MoreAnalysis of Fancy Light greenish yellow diamond leads to detection of nickel, as well as an inclusion that gives a colour-change effect.
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