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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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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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Explores statistical data and defining characteristics of gem-quality CVD synthetic diamonds examined by GIA since 2003.
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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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Analyses the chemical composition and inclusion characteristics of this ancient artefact.
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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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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.
Read MoreProvides a visual guide to the internal features of natural, synthetic and treated rubies.
Read MoreCompares 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).
Read MorePresents 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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