Koroit Boulder Opal

This 293 gram parcel contains 10 Koroit boulder opal matrix rubs sourced from the Koroit opal field in Queensland, Australia. These are large, thick pieces showcasing the natural patterns and formations that make Koroit matrix material so popular with collectors and lapidary artists worldwide.

The dominant character of this parcel is warm golden amber and honey colored ironstone with natural web and network patterns running across the polished faces. Bright teal and green opal veining traces through the ironstone on nearly every piece, following the natural fracture lines and creating an organic contrast against the warm brown tones. Several pieces display the classic Koroit concentric ring pattern where opal has filled circular formations within the ironstone, showing bands of purple, red, and amber radiating outward from a central point.

The largest piece in the lot features a dramatic network of purple and red veining across its surface, resembling a natural mosaic. Two smaller pieces on the right and bottom left show cross sections of Koroit nut formations with layered concentric rings of purple and amber.

At 293 grams across 10 pieces, this parcel offers a substantial amount of Koroit matrix material. Each piece has enough thickness and surface area to yield polished cabochons, or they can be appreciated as natural display specimens in their current form.

All 10 opals are 100% natural and completely untreated. These are not doublets or triplets. Photographs were taken wet under LED lighting. Dry appearance will differ. Price includes worldwide registered shipping.

This collection will arrive securely packaged in an Opal Galaxy gift box, making it ready for safe storage, jewelry setting, or presentation as a collector gemstone.

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