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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Characterisation of Mg and Fe Contents in Nephrite Using Raman Spectroscopy
Xiaoyan Feng, Yong Zhang, Taijin Lu, and Hui Zhang, August 7, 2017
Evaluates the usefulness of Raman spectroscopy in distinguishing the colour varieties of nephrite based on the relative ratio of Mg to Fe concentration.
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Cuprian Liddicoatite Tourmaline
Yusuke Katsurada and Ziyin Sun, May 8, 2017
Identifies 13 copper-bearing tourmalines, which have traditionally been assumed to be elbaite species, as liddicoatite.
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Characteristics of Gem-Quality By-Product Synthetic Zincite
Ji Zhang, Yujie Gao, and Guanghai Shi, May 8, 2017
Investigates the properties of synthetic zincite produced by industrial kilns in Poland.
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