Article Search Results

Separation of Black Diamond from NPD Synthetic Diamond

Paul Johnson and Kyaw Soe Moe, August 3, 2016

DiamondView is used to differentiate a Fancy black natural diamond from its NPD synthetic counterparts.

Article

Spring 2015 G&G Examines Blue Spinel, Chinese Jewellery Design and the Latest in Synthetics

Russell Shor, June 12, 2015

G&G Brief presents an overview of the content of the Spring 2015 issue of Gems & Gemology.

CVD Synthetic Diamond with Fancy Vivid Orange Colour

Wuyi Wang and Kyaw Soe Moe, January 30, 2015

Strong absorptions from N-V centres were the main cause of a CVD synthetic diamond’s pinkish orange bodycolour.

Xenotime Inclusion in Yellow Diamond

Kyaw Soe Moe, Martha Altobelli, and Paul Johnson , October 31, 2014

Presents what is believed to be the first report of a xenotime inclusion in gem-quality diamond.

Mixed-Type Cape Diamond

Martha Altobelli and Paul Johnson , October 31, 2014

A Fancy orangey-yellow “cape” diamond featured an unexpected 480 nm band, a defect normally associated with orange colour.

Large synthetic moissanite with silicon carbide polytypes

Kyaw Soe Moe, Paul Johnson, and Ren Lu, January 31, 2014

Examination of the properties of a synthetic moissanite specimen submitted as a black diamond.

Black diamond with unusual colour origin

Troy Ardon, January 31, 2014

This black diamond's colour was produced by natural radiation stains, an unusual cause of colour.

Strong Colour Zoning in Diamond Reflects Complex Growth Environment

Troy Ardon, GIA, July 1, 2013

A report on a 2.08 ct emerald-cut diamond graded as fancy dark orangey brown.

A Large Irradiated Green-Yellow Diamond

Wuyi Wang, Paul Johnson, and Emiko Yazawa, GIA, July 1, 2013

GIA's identification of a large diamond as artificially irradiated based on careful spectroscopic analysis and lab database review.

Confusing, Triangular Inclusions in an Art Deco-Style Pin

Spring 1991 G&G Lab Notes

March 1, 1991

This section, from the Spring 1991 issue of Gems & Gemmology, is a compilation of interesting finds from GIA’s laboratories.

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