87.6 ct Rare Tribal Queensland Boulder Opal From Historic Andreou Heritage Collection

This exceptional 87.6 ct double-sided Queensland boulder opal is a true living work of museum-quality natural art, displaying rich tribal patterning with dynamic play-of-color revealed from both faces. Held for a full generation within the Andreou Family Heritage Collection, this rare opal originates from an era of Australian opal mining that can no longer be replicated. Its scale, bilateral color performance, and preserved provenance elevate it beyond a gemstone into a historic artifact — a one-of-a-kind opportunity for the serious collector or institution.