Australian Boulder Opal Specimen – Polished, 170x45x45mm, 0.67kg

This Australian Boulder Opal specimen is a polished, hand-sized piece of ironstone carrying natural veins of opal colour throughout. A rich reddish-brown matrix is threaded with pale cream fracture lines, and blue-green flashes of precious opal run through the cracks and fissures where silica once filled the stone's natural voids — a visible record of how boulder opal forms. The surface has been polished to a smooth, rounded finish that shows the ironstone's colour changes and the opal veins clearly from every angle. Because the opal here runs through the matrix rather than sitting as a single cut face, this piece reads more as a mineral specimen than a cut stone — ideal for a collector's shelf or display cabinet.

About Boulder Opal

Boulder opal forms as veins of precious opal within ironstone matrix in the opal fields of Queensland — primarily Quilpie, Yowah and Winton. Unlike black opal from Lightning Ridge, the opal cannot be separated from its host rock; it's cut as a single solid piece, with the natural brown ironstone remaining as the stone's backing. This gives boulder opal its distinctive look — vivid colour against rich earth tones — and also makes it physically more durable than other opals, since the ironstone host is harder than the opal layer it carries.

Specifications

• Stone: Boulder Opal (natural ironstone matrix)
• Weight: 0.67kg
• Dimensions: 170 x 45 x 45mm
• Finish: Polished
• Matrix: Ironstone
• Origin: Queensland, Australia
• Availability: One-of-a-kind — 1 piece available

Caring for Your Opal Specimen

Boulder opal is more durable than solid opal because of its ironstone backing, but it's still worth a little care. Handle by the body of the piece, keep it away from sudden temperature swings, and avoid knocking it against hard surfaces when moving or displaying it. Dust with a soft, dry cloth; if a deeper clean is needed, wipe gently with a barely damp cloth rather than soaking it. Keep away from direct, prolonged heat sources.

Provenance

Hand-selected by Joseph Bernecki, sourced direct from the Australian opal fields and set in his Sydney workshop. Meet him any weekend at The Rocks Market, stall under the bridge, Sydney. Read Joseph's story →

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