6.85 Ct 3D Wood Replacement Opal Tucson A lovely small purple boulder

A lovely small purple boulder opal specimen

88 Ct wood replacement opal in a classic rectangle shape

Mined by Sue at her Mt

perfect for a ring or pendant

A larger boulder opal heart with a thick green-blue opal stripe

6.85 Ct 3D Wood Replacement Opal Tucson A lovely small purple boulderA stunning 6. 85 Ct wood replacement opal in a classic oval shape. 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