Australian Boulder Opal Rough is mined over thousands of square kilometers in central Queensland Australia. Below is a chart showing many of the amazing types of Rough Boulder Opals that have been found and mined in Australia.
The major Opal fields are Winton, Quilpie, Yowah, Korit, Opalton with many opal mines hundreds of kilometers away from any regional town. So if you meet an opal miner and he invites you to his mine you are best to take provisions for a 2 day drive! Some boulder opal is even mined closed to the Northern territory border. Many Opal cutters will specialize in one particular area as boulder opal is found in veins in bedrock and has to be split or sawn or chipped open to expose opal colors.
Most Boulder Opal is sedimentary so it is not cabochon but some colors and pattern are spectacular and opal splits make ideal earrings.
Lightning Ridge Opal needs water to clean the Rough Opal but Boulder Opal is found in more desert conditions and water is scarce even though the Artesian water trough is close by. To combat the lack of water dry agitators are commonly used to expose Opal veins in the host bed rock and bulldozers work well in these hot dry dusty conditions.
Diesel fuel is expensive now and many Opal miners spend thousands dollars each week on fuel so Opal is getting more expensive to mine and harder to find large deposits of Boulder Opal.
Was this article helpful?5 people found this article helpful