8.22 Ct 3D wood replacement opal Tucson A lovely small teardrop boulder

A lovely small teardrop boulder opal from our inexpensive range

A pastel rainbow boulder opal heart with a striped pattern

A gorgeous purple boulder opal with flecks of green

22 Ct wood replacement opal with a half-circle shape and soft corners

A beautiful green and purple striped boulder opal

8.22 Ct 3D wood replacement opal Tucson A lovely small teardrop boulderA lovely 8. 22 Ct wood replacement opal with a half circle shape and soft corners. 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