Boulder Opal
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 · Source: Average of mid-range boulder opal prices from gemstone retailers; typical retail…
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.
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