Article Search Results

A face-up view of a cushion cut diamond with blue color.

Article

Gems & Gemology’s 7 Most Unusual Encounters from 2019

Stuart Overlin, Brooke Goedert and Kellie Giordano, December 13, 2019

Check out some of the most interesting and unusual diamonds and coloured stones submitted to GIA’s laboratories in 2019.

A row of various shaped cut and polished pink diamonds.

Article

Why are Pink Diamonds Pink? GIA Researchers Dive Deep into their Crystal Structure

Russell Shor, October 18, 2019

GIA researchers analysed more than 90,000 natural pink diamonds to better understand how these rare and beautiful diamonds formed and got their colour.

Yellow HPHT-Processed Rough Diamond

Sally Chan, November 23, 2015

HPHT annealing of a nearly eye-clean yellow natural rough diamond is revealed through spectroscopic analysis.

4.29 ct color-treated Fancy brown-pink diamond

Treated Pink Type IIa Diamond Coloured by Red Luminescence

Sally Eaton-Magaña, November 7, 2016

A type IIa colour-treated diamond was graded as Fancy brown-pink under daylight conditions and Fancy purplish grey under incandescent lighting, a colour change that resulted from HPHT annealing and irradiation.

Natural Fancy pink diamond with apparent HPHT synthetic growth structure.

Treated Pink Diamond with HPHT Synthetic Growth Structure

Kyaw Soe Moe and Wuyi Wang, February 1, 2016

A Fancy pink type IIa diamond showing cuboctahedral growth and greenish blue phosphorescence is shown to be a natural, treated coloured diamond.

59.88 ct Fancy Vivid yellow irradiated diamond

Very Large Artificially Irradiated Yellow Diamond

Christopher Vendrell and Paul Johnson, November 7, 2016

Examination of a 59.88 ct irradiated yellow diamond, one of the largest irradiated diamonds identified by GIA.

DiamondView image of pink diamond showing two pink spots near the edge of the table facet

Evidence of Focused Beam Irradiation in Treated Pink Diamond

Troy Ardon and Lorne Loudin, November 7, 2016

DiamondView imaging and photoluminescence spectroscopy offered evidence of focused beam irradiation in a pink diamond.

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

Article

Autumn 2015 G&G: Trapiche Emeralds, Synthetic Diamonds and a Large Diamond Source

Russell Shor, November 4, 2015

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

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.

Article

Summer 2015 G&G: Dual-Stars, Photomicrography Guide, Rubies from Tajikistan, New Micro-World Section

Russell Shor, August 14, 2015

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

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