Part-9 Opal Dictionary
Opal Dictionary
Andamooka:
Mining Area in South Australia. Producing Crystal Opal and treating matrix opal.
Assembled Opal:
Opal that has been glued together, also known as mosaic opal.
Boulder Opal:
Formed in cavities and cracks of ironstone, usually from Queensland, Australia.
Black Opal:
Naturally occurring rare and valuable solid opal formed in Ironoxide found in Lightning Ridge in Northern NSW.
Black Crystal Opal:
Solid black opal which is transparent due to little or no iron oxide on the back. Viewed from the top, it compares at least with N3 in darkness rating.
