Article
GIA Researchers Reveal the Secrets of Diamond-in-a-Diamond Mystery
Stephen Morisseau, January 13, 2020
GIA researchers in New York recently had the opportunity to examine one of the most interesting and unique diamond crystals ever found.
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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.
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Article
Inside De Beers’ Lightbox Diamonds
Russell Shor, March 18, 2019
GIA researcher analyses and confirms that De Beers’ Lightbox diamonds are grown using the chemical vapour deposition process.
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An Early Byzantine Engraved Almandine from the Garibpet Deposit, Telangana State, India: Evidence for Garnet Trade Along the Ancient Maritime Silk Road
H. Albert Gilg, Karl Schmetzer, and Ulrich Schüssler, August 6, 2018
Analyses the chemical composition and inclusion characteristics of this ancient artefact.
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Gemmological Characterisation of Sapphires from Yogo Gulch, Montana
Nathan D. Renfro, Aaron C. Palke, and Richard B. Berg, August 6, 2018
A look at the mining and distinguishing characteristics of this naturally vibrant blue sapphire.
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Accurate Reporting of Key Trace Elements in Ruby and Sapphire Using Matrix-Matched Standards
Jennifer Stone-Sundberg, Timothy Thomas, Ziyin Sun, Yunbin Guan, Zachary Cole, Randy Equall, and John L. Emmett, January 26, 2018
Presents a group of corundum standards developed by GIA to improve the accuracy and efficiency of its laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) instruments.
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True Colours of “Dalmatian Jasper”
Tomasz Powolny and Magdalena Dumańska-Słowik, November 8, 2017
Discusses the mineralogical composition and provenance of this spotted decorative gemstone.
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Photoluminescence Spectra of Emeralds from Colombia, Afghanistan and Zambia
D. Brian Thompson, Christian J. Bayens, Matthew B. Morgan, Taylor J. Myrick, and Nealey E. Sims, November 8, 2017
Compares PL spectroscopy data of 48 emerald samples from three countries to evaluate the usefulness of the technique in geographic origin determination.
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The Very Deep Origin of the World’s Biggest Diamonds
Evan M. Smith, Steven B. Shirey, and Wuyi Wang, November 8, 2017
Explores an exceptional family of diamonds, referred to as “CLIPPIR” (Cullinan-like, Large, Inclusion-Poor, Pure, Irregular and Resorbed), that formed in a super-deep environment.
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Synthetic Star Sapphires and Rubies Produced by Wiede’s Carbidwerk, Freyung, Germany
Karl Schmetzer, H. Albert Gilg, and Heinz-Jürgen Bernhardt, November 8, 2017
Details the process used by Wiede’s Carbidwerk to produce star synthetic corundum from the mid-1950s until the 1970s.
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