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.

Article

Autumn 2016 G&G: CVD Synthetic Diamonds Survey, Reversible Colour Change in Blue Zircon

Jennifer-Lynn Archuleta, October 31, 2016

A summary of the content found in the Autumn 2016 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.

This specimen was revealed to be a synthetic star sapphire.

Synthetic Sapphire with Diffusion-Induced Colour and Star

Sutas Singbamroong, Nazar Ahmed, and Nahla Al Muhairi, July 31, 2015

Diffusion treatment is used to induce colour and asterism in a colourless synthetic sapphire.

Article

Update on the Rock Creek Sapphire Deposit

Warren Boyd, June 17, 2015

An overview of recently expanded sapphire production at the Gem Mountain mine near Philipsburg, Montana.

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.

Green Sapphire Filled with Glass

Phil York, October 17, 2013

Analysis reveals blue lead glass filling in a sapphire that has an overall green bodycolour as a result of the filling’s combination with natural yellow colour.

Beryllium Diffusion of Ruby and Sapphire

John L. Emmett, et al., June 1, 2003

The heat treatment of corundum involving lattice diffusion of beryllium (Be) at temperatures over 1800°C has become a major issue in the gem trade.

Heat Treating the Sapphires of Rock Creek, Montana

John L. Emmett and Troy R. Douthit, September 1, 1993

Renewed interest in large-scale commercial mining of Montana sapphires motivated a detailed study of the heat treatment of sapphire from the Rock Creek deposit.

Update on Diffusion-Treated Corundum: Red and Other Colours

Shane F. McClure, Robert C. Kammerling, March 1, 1993

Blue diffusion-treated sapphires have become a subject of considerable controversy since their introduction in significant quantities a few years ago.

Article Search Results

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Gemstones

Article Search Results

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Gemstones

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