Australian Boulder Opal
Natural Australian boulder opal is Queensland’s signature gemstone, formed millions of years ago when silica rich water filled cracks inside host ironstone boulders. Because the natural host rock is left on the back during cutting, boulder opal is durable and displays a vibrant play of color against a dark, earthy base. This collection showcases authentic, untreated solid boulder opals sourced directly from famous fields such as Winton and Koroit.
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Frequently Asked Questions
What is boulder opal?
Boulder opal is precious opal naturally fused to its brown ironstone host rock.
Where does boulder opal come from?
All natural boulder opal comes from western Queensland fields including Winton, Koroit, and Yowah.
Is the ironstone backing real?
Yes, the backing is the natural host rock and is completely organic, never artificially glued.
Is boulder opal durable?
Boulder opal is the most durable solid opal variety due to the supportive ironstone backing.
How is boulder opal valued?
Value depends on face color brilliance, patterns, size, and minimal ironstone intrusion on the surface.