Learn about the differences – and similarities – between natural and laboratory-grown diamonds, and how GIA’s researchers and grading laboratories can tell the difference
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A marquise-cut diamond is found to have been broken and reassembled with an unknown adhesive.
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A report on the largest facet-grade afghanite seen in the GIA gem identification department.
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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 MoreBeads appearing to be ruby-in-zoisite are revealed to be dyed quartzite.
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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