8.23 Ct wood replacement opal Price_Mid-range A beautiful blue and green

A beautiful blue and green triangle boulder opal

A gorgeous green-blue boulder opal

A beautiful pill-shaped boulder opal with bright green and blue colours

We don't get these very often

Three lovely small dark purple boulder opal pieces

8.23 Ct wood replacement opal Price_Mid-range A beautiful blue and greenA stunning green, blue and purple wood replacement opal. What is Wood Replacement opal? Opal formation commences when silica dissolves in water. At our Russells opal mine we have found that this silica solution occupies a void most probably left by decaying tree roots or branches. In cases where the silica infiltrates organic material before complete decomposition occurs, the organic molecules are replaced by silica. This remarkable process results in