Boulder Opal
$500
Boulder opal is a gemstone formed within ironstone matrix, primarily mined in Queensland, Australia, valued for its vibrant color play and unique appearance.
Estimated value as of 2026 路 Source: https://thewindopal.com/blogs/opal-news/how-much-does-boulder-opal-cost
Fun Fact
Boulder opals are unique because the host ironstone rock is left intact as part of the finished gemstone, creating a naturally dark backdrop that enhances the stone's color flashes and fire.
Price History
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