Opal’s play-of-colour is a lyrical dance: sometimes a grand jeté of bold, broad flashes of colour or smaller, quicksteps of pinpoint flashes.
Read MoreLearn how the structure, inclusions and properties of some gemstones interact with light to create unusual visual effects.
Read MoreG&G Brief presents an overview of the content of the Winter 2015 issue of Gems & Gemology.
Read MoreAn opal featuring a rare six-rayed star is examined in GIA's Bangkok lab.
Read MoreA simple test easily detected dye treatment in fire opal.
Read MoreThis article, from the Winter 2009 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.
Read More“Leopard opal” consists of vesicular basalt impregnated with play-of-colour opal, and is known only from Zimapán, Hidalgo State, Mexico.
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