opal

“Harlequin Prince” black opal, 215.85 cts, Lightning Ridge, American Museum of Natural History. Photo by greyloch. Licensed under…

This black opal shows a wide range of colors. Stayish Mine, Wollo Province, Ethiopia. Photo by James St. John. Licensed under CC By 2.0.

Peruvian opal wire-wrapped ring with brass band. Photo by Zoe. Licensed under CC By 2.0.

This 15.5-carat double cabochon opal has a flash of color across its entire face. Tsehay Mewcha, Wollo, Welo Province, Ethiopia. © Rob Lavinsky,…

Diamond and gold pendant with 19.9-ct Ethiopian Welo opal. Photo by Dpulitzer. Licensed under CC By-SA 4.0.

Synthetic opal. Photo by Christian Schröder. Licensed under CC By-SA 3.0.

Precious opal from the Slovak Republic, Slanské hills, village Červenica site – Libanka. Photo by Ivan Kopor. Licensed under CC By-SA 3.0.…

Black opal, Australia (stone in bracelet ~ 20 carats). Photo © Joel E. Arem, PhD, FGA. Used with permission.

14-ct, faceted Welo opal with honeycomb structure. © Mark Oros, Hashnu Stones & Gems. Used with permission.