Review of Exotic Gems, Vol. 3: How to Identify, Evaluate, Select and Care for Matrix Opal, Fire Agate, Blue Chalcedony, Rubellite Indicolite, Paraíba and Other Tourmalines, by Renee Newman.

Ahmadjan Abduriyim receives 2021 JAMS award for his contributions to applied mineralogy.

An examination of play-of-color opal from Mexico and its variety of inclusions.

The first documented UV-reactive chemical treatment to make opal appear tenebrescent.

The natural-color oolitic opal is the largest of its type examined by GIA.

Play-of-color patches in black opal display interesting written character patterns.

Black Opal Direct’s use of social media increases sales during the COVID-19 pandemic.

Opal was the focus of the April 2015 Sinkankas Symposium at GIA’s Carlsbad, California campus.

Material from a new opal deposit in Morelia, Mexico is examined.

Commercial quantities of gem-quality chrysoprase and green prase opal (nickel-bearing chalcedony and common opal, respectively) have been recovered from altered serpentinite deposits near Haneti, Tanzania.