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This Month's
Characterization of Montana Sapphire
Examines the mining history and geological characteristics of the three secondary sapphire deposits in the state of Montana, as well as the properties of these sapphires (unheated and heat-treated).
GIA Knowledge Sessions
Engage in webinars on the most diverse and pressing issues in gemology today, including gemstone origin, laboratory-grown stones and new discoveries in field gemology.
Purple Anhydrite
The Carlsbad laboratory encounters its first example of a transparent purple faceted single crystal anhydrite.
Starry Night in Diamond
Cloud inclusions resembling stars at night are observed in a faceted diamond.
Plastic Deformation: How and Why Are Most Diamonds Slightly Distorted?
A look at plastic deformation, one of the most prevalent features in natural diamond.