Article
DNA Techniques Applied to the Identification of Pinctada Fucata Pearls from Uwajima, Ehime Prefecture, Japan Supplementary Data
Kazuko Saruwatari, Michio Suzuki, Chunhui Zhou, Promlikit Kessrapong, and Nicholas Sturman, May 11, 2018
Shows how genetic material extracted from small amounts of pearl powder can be a useful indicator of this akoya cultured pearl species.
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Article
Observations on the Heat Treatment of Basalt-Related Blue Sapphires
Wasura Soonthorntantikul, Charuwan Khowpong, Ungkhana Atikarnsakul, Sudarat Saeseaw, Supharart Sangsawong, Wim Vertriest, and Aaron Palke, May 1, 2019
Researchers from GIA’s Bangkok laboratory seek to identify low-temperature heat treatment in basalt-related blue sapphires.
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Article
Characterization of Blue Sapphires from the Mogok Stone Tract, Mandalay Region, Burma (Myanmar)
Ungkhana Atikarnsakul, Wim Vertriest and Wasura Soonthorntantikul, June 6, 2018
The Mogok Stone Tract of central Myanmar (Burma) is one of the world’s most famed sources of colored stones, particularly ruby, sapphire, and spinel.
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Article
Non-Bead-Cultured Pearls from Pinctada margaritifera
Nanthaporn Nilpetploy, Kwanreun Lawanwong, and Promlikit Kessrapong , April 30, 2018
A new report from GIA's Bangkok laboratory, "Non-Bead-Cultured Pearls from Pinctada margaritifera," examines a set of 120 NBC samples stated to be of "Tahitian" origin.
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Article
Update on "Low-Temperature" Heat Treatment of Mozambican Ruby: A Focus on Inclusions and FTIR Spectroscopy
Sudarat Saeseaw, Boodsakorn Kongsomart, Ungkhana Atikarnsakul, Charuwan Khowpong, Wim Vertriest, and Wasura Soonthorntantikul , April 30, 2018
GIA's Bangkok laboratory recently performed heat treatment experiments on 47 Mozambican rubies mined in Mugloto.
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Article
A Study of Sapphire from Chanthaburi, Thailand and its Gemological Characteristics
Sudarat Saeseaw, Supharart Sangsawong, Wim Vertriest, Ungkhana Atikarnsakul, Victoria Liliane Raynaud-Flattot, Charuwan Khowpong, and Vararut Weeramonkhonlert, April 19, 2017
A report from the GIA Laboratory in Bangkok presents their findings on 59 blue sapphire samples obtained from a miner in the Khao Ploy Waen area, Chanthaburi.
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Article
Atypical “Beading” in the Production of Cultured Pearls from Australian Pinctada Maxima
Kenneth Scarratt, Nicholas Sturman, Abeer Tawfeeq, Peter Bracher, Michael Bracher, Artitaya Homkrajae, Areeya Manustrong, Nanthaporn Somsa-ard, and Chunhui Zhou, February 13, 2017
In 2011, the authors began to see cases of low-quality natural pearls being used as unconventional “beads” for cultured nacre growth.
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Article
An In-Depth Gemological Study of Blue Sapphires from the Baw Mar Mine (Mogok, Myanmar)
Wasura Soonthorntantikul, Wim Vertriest, Victoria Liliane Raynaud-Flattot, Supharart Sangsawong, Ungkhana Atikarnsakul, Charuwan Khowpong, Vararut Weeramonkhonlert, and Vincent Pardieu, February 24, 2017
GIA field gemologists visited Baw Mar operations in 2013, 2014, and 2015. In this study, we analyzed samples collected during two separate expeditions.
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Article
An In-Depth Gemological Study of Blue Sapphires from Pailin, Cambodia
Sudarat Saeseaw, Supharart Sangsawong, Wim Vertriest, and Ungkhana Atikarnsakul , December 22, 2017
A report from GIA Laboratory in Bangkok analyzing 68 blue sapphires from Pailin, Cambodia.
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Article
Analysis of Synthetic Ruby Overgrowth on Corundum
Sudarat Saeseaw, Vincent Pardieu, Vararut Weeramonkhonlert, Supharat Sangsawong, and Jonathan Muyal, June 25, 2015
Analysis of synthetic ruby overgrowth on corundum, using analysis of inclusions, UV-Vis-NIR and EDXRF spectroscopy, and LA-ICP-MS.
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