Identification of “Pistachio” Coloured Pearls Treated by Ballerina Pearl Co.
Chunhui Zhou, Joyce Wing Yan Ho, Sally Chan, Jessie Yixin Zhou, Surjit Dillon Wong, and Kyaw Soe Moe, April 28, 2016
A report on the colour treatment process for these intensely greenish yellow to yellowish-green cultured pearls and the techniques for identifying them.
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Variscite from Central Tajikistan: Preliminary Results
Andrey K. Litvinenko, Elena S. Sorokina, Stefanos Karampelas, Nikolay N. Krivoschekov, and Roman Serov, April 28, 2016
A look at the gemmological properties and chemical composition of this light blue to light green to green gem material, which is suitable for cabochon cutting.
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Observations on CVD-Grown Synthetic Diamonds: A Review
Sally Eaton-Magaña and James E. Shigley, November 7, 2016
Explores statistical data and defining characteristics of gem-quality CVD synthetic diamonds examined by GIA since 2003.
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An Introduction to Photoluminescence Spectroscopy for Diamond and Its Applications in Gemmology
Sally Eaton-Magaña and Christopher M. Breeding, April 28, 2016
Presents the underlying physics and methodology of this analytical technique, which has become an essential tool in identifying treated and synthetic diamonds.
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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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Black Diamonds from Marange (Zimbabwe): A Result of Natural Irradiation and Graphite Inclusions
Karen V. Smit, Elina Myagkaya, Stephanie Persaud, and Wuyi Wang, August 6, 2018
Characterises a suite of 40 natural brown to black diamonds from this deposit so that they can be distinguished from suspected treated black diamonds.
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Natural-Colour Blue, Grey and Violet Diamonds: Allure of the Deep
Sally Eaton-Magaña, Christopher M. Breeding, and James E. Shigley, August 6, 2018
Summarises data collected on more than 15,000 natural blue/grey/violet diamonds examined by GIA during the last decade and examines the mechanisms that produce this colour range.
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Inclusions in Natural, Synthetic and Treated Ruby
Nathan D. Renfro, John I. Koivula, Jonathan Muyal, Shane F. McClure, Kevin Schumacher, and James E. Shigley, January 26, 2018
Provides a visual guide to the internal features of natural, synthetic and treated rubies.
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Real-Time Microradiography of Pearls: A Comparison Between Detectors
Stefanos Karampelas, Abeer Tawfeeq Al-Alawi, and Ali Al-Attawi, January 26, 2018
Compares the image quality provided by real-time microradiographic imaging (RTX) units fitted with two different detectors: an image intensifier (II) and a flat panel detector (FPD).
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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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