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This Month's
Optical Whitening and Brightening of Pearls: A Fluorescence Spectroscopy Study
READ MOREExceptional Purple Montana Sapphire
A particularly fine unheated purple Montana sapphire is noted for both its size and its multiple diverse inclusions.
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.
Quarterly Crystal: Pyrite in Quartz
Bright and brassy crystalline pyrite inclusions add interest to a fine specimen of Colombian rock crystal quartz.
Purplish Pink Diaspore Reportedly from Afghanistan
An attractive new purplish pink color of gem-quality diaspore comes to the market.
HPHT-Processed CVD Laboratory-Grown Diamonds with Low Color Grades
The Antwerp lab examines CVD laboratory-grown diamonds where HPHT processing resulted in relatively low color grades.
Marble Imitation of Jadeite Rough
A stone submitted as rough jadeite proves upon analysis to be marble, indicative of the increasing use of imitations in the jewelry market.