Boulder Opal - Bigger & More Unusual Than You Think! — Koroit!
10:34
Subtle Flaw - Big Problem in this Australian Opal!
18:51
Selecting~Sawing and Cutting Boulder Opal
18:59
Australian Opal patterns explained
6:58
The Opal Whisperers Celebrate Finding Over 150KG's of Rare Opal Stones
13:06
Glowing rough opal has the potential to cut a top gem
12:26
Rough opal cuts, converts into a profit
11:54
Boulder Opal Mining Koroit June 2016
5:12