Purplish Pink Spinel from Tajikistan: Before and After Cutting
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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This article, from the Summer 2009 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.
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Gem-quality rubies and pink to purple sapphires are being recovered from the Luc Yen and Quy Chau mining regions of Vietnam.
Read MoreThis article reports the results of a series of experiments conducted to explain the phenomenon of induced fingerprints.
Read MoreThe authors determined that there are actually seven types of "yellow" sapphire on the market today, which differ in the cause of colour and the stability of the colour to light.
Read MoreToday, only by combining different gemmological tests with years of practical experience, can a conclusive determination of the origin of a sapphire be made.
Read MoreMost Russian hydrothermal synthetic rubies and pink, orange, green, blue and violet sapphires—coloured by chromium and/or nickel—reveal diagnostic zigzag or mosaic-like growth structures associated with colour zoning.
Read MoreBlue sapphires from China are similar to gem corundum from Australia, Thailand, and Kampuchea (Camodia).
Read MoreGreater amounts of colourless sapphire—promoted primarily as diamond substitutes, but also as natural gemstones—have been seen in the gem market during the past decade.
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