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Water Immersion Reveals Dye in Fire Opal
Social Media Success for Black Opal Direct
Black Opal Direct’s use of social media increases sales during the COVID-19 pandemic.
Written Characters in Black Opal
Play-of-color patches in black opal display interesting written character patterns.
Large Oolitic Opal Block
The natural-color oolitic opal is the largest of its type examined by GIA.
UV-Reactive Opal
The first documented UV-reactive chemical treatment to make opal appear tenebrescent.
Ahmadjan Abduriyim Receives JAMS Award for Applied Mineralogy
Ahmadjan Abduriyim receives 2021 JAMS award for his contributions to applied mineralogy.
Opal from Queretaro, Mexico: Occurrence and Inclusions
An examination of play-of-color opal from Mexico and its variety of inclusions.
New Deposits of Gem-Quality Common Opal from Michoacán, Mexico
Material from a new opal deposit in Morelia, Mexico is examined.
2015 Sinkankas Symposium
Opal was the focus of the April 2015 Sinkankas Symposium at GIA’s Carlsbad, California campus.
Green Opal From East Africa
Lepidocrocite in Boulder Opal
A boulder opal contained an unusual carpet of needle-like lepidocrocite inclusions along the interface between the opal and the ironstone matrix.
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