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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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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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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Fluorescence produced by optical defects in diamond: measurement, characterisation and challenges
Yun Luo, July 24, 2013
How variations in UV lamp output can affect observed fluorescence colour and intensity.
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Characterisation of “Green Amber” With Infrared and Nuclear Magnetic Resonance Spectroscopy
Ahmadjan Abduriyim, et al.
A peridot-like bright greenish yellow to green gem material called “green amber” has recently appeared in the gem market.
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X-ray Computed Microtomography: Distinguishing Natural Pearls from Beaded and Non-Beaded Cultured Pearls
The distinction of natural from cultured pearls has traditionally been based on X-radiography.
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Spectral Differentiation Between Copper and Iron Colourants in Gem Tourmalines
Paul B. Merkel and Christopher M. Breeding
The authors used Vis-NIR spectral measurements combined with LA-ICP-MS data to investigate the usefulness of absorption spectra.
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X-ray Computed Microtomography Applied to Pearls: Methodology, Advantages and Limitations
Stefanos Karampelas, Jürgen Michel, Mingling Zheng-Cui, Jens-Oliver Schwarz, Frieder Enzmann, Emmanuel Fritsch, Leon Leu, and Michael S. Krzemnicki
X-ray computed microtomography reveals the internal features of pearls in great detail.
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The “Type” Classification System of Diamonds and Its Importance in Gemmology
Christopher M. Breeding and James E. Shigley, June 1, 2009
Knowledge of type allows gemmologists to better evaluate if a diamond might be treated or synthetic, and whether it should be sent to a laboratory for testing.
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