Australian Boulder Opal Specimen – 0.97kg, Green & Blue Colour Play

At just under a kilogram, this Australian boulder opal specimen is one of the larger pieces in the collection — a substantial freeform stone with real weight and presence in the hand. One face has been polished to reveal a wide sweep of colour: turquoise, sky blue and soft cream moving across the stone in broad bands, with the ironstone matrix showing through as darker patches within the colour itself rather than sitting only at the edges. The reverse keeps its natural rounded ironstone surface, with just a narrow seam of blue visible where the opal layer runs close to the surface. At 125 x 90 x 60mm and 0.97kg, it's a specimen built to be picked up and turned in the light rather than just looked at from one angle.

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: Natural Australian Boulder Opal
• Weight: 0.97kg
• Dimensions: 125 x 90 x 60mm
• Colour Play: Green and blue
• Matrix: Ironstone
• Form: Freeform, part-polished specimen
• Origin: Queensland, Australia
• Availability: One-of-a-kind — 1 piece available

Caring for a Display Specimen

Boulder opal is naturally more robust than solid opal because of its ironstone backing, but it's still a natural stone worth handling with a little care. Pick it up by the matrix rather than gripping the polished face, keep it somewhere stable where it won't be bumped off a shelf, and avoid sitting it in direct sun or right next to a heater — like any opal, sudden swings in temperature aren't ideal. A soft, dry cloth is all it needs to stay clean.

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 →

Common Questions