Oregon Sunstone | Faceted Swirl Briolette Set | USA | Three Stone Lot | OSB113

Oregon Sunstone is the official state gemstone of Oregon, mined exclusively from the volcanic basalt flows of Harney and Lake Counties — one of the only gem feldspar deposits in the world where native copper is responsible for both color and optical phenomenon. That copper content produces schiller, an aventurescent effect in which microscopic copper platelets suspended within the crystal reflect light in a bold, shifting metallic flash that moves and changes as the stone is rotated. All three stones in this set display schiller, and ranging from 13mm to 16mm in length at a combined weight of 8.7 carats, the depth of material through which light travels to interact with those copper platelets is substantial — producing a schiller display of a richness and intensity that smaller stones simply cannot achieve.

These briolettes feature the same distinctive swirl or twist faceting pattern that wraps around the circumference of each stone — an uncommon and highly skilled lapidary treatment that creates a dynamic, multidirectional light return interacting with the schiller across multiple planes simultaneously as the stones move. Cross-drilled at the top, all three are ready for immediate use, and their sizing lends itself naturally to a coordinated earring and pendant suite — the two closer-matched stones pairing as drops while the third anchors a pendant centerpiece, or arranged as a graduated trio across a single design. At 13 x 8mm, 16 x 7mm, and 13 x 6.5mm the subtle variation in proportions adds an organic, collected quality to the set rather than the uniformity of mass-produced components. Oregon Sunstone briolettes of this size, cut complexity, and schiller quality are exceptionally rare — a swirl-faceted set of three in domestic sunstone, suited for a complete jewelry suite, is a find that is unlikely to be replicated once gone.

DETAILS
Origin: Oregon, USA
Species: Feldspar
Variety: Oregon Sunstone (Andesine-Labradorite)
Cut: Faceted Swirl Briolette, Cross-Drilled
Size: 13 x 8mm / 16 x 7mm / 13 x 6.5mm
Weight: 8.7 ct total (three stone set)
Sold: Three Stone Lot
Treatment: None
Hardness: 6 – 6.5 (Mohs)
Refractive Index: 1.559 – 1.568