Opal Stone – Natural, Cabochon, Black
This Andamooka matrix opal certainly resembles fine black opal. However, if you look closely at the black areas you'll see this matrix opal received a sugar-acid treatment. "Andamooka matrix opal," photo by Dpulitzer. Licensed under CC By-SA 3.0.
Article: Opal Treatments: How to Detect Treated Opals
Credit: Dpulitzer
Gemstone | Opal Stone |
Natural or man made | Natural |
Gem State | Cabochon |
Color | Black |
Transparency | Translucent |
Photo phenomena | Play of Color |