mineral

Polished brown jasper (likely brecciated or orbicular jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide inclusions

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; opaque brown, golden, black, and rusty-red coloration; vitreous to waxy luster when polished; cryptocrystalline quartz with no visible cleavage and conchoidal fracture. The rounded shape indicates tumbling or polishing.

Identified September 2, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater replaces or fills cavities in volcanic or sedimentary materials, with iron oxides producing the brown and red colors. Deposits commonly formed during the Cenozoic or older volcanic episodes, depending on locality.

Uses & applications

Used for cabochons, beads, carvings, decorative objects, and lapidary collections; too opaque for most faceted gemstone use.

Geological facts

Jasper is an opaque variety of chalcedony distinguished from agate by its substantial opacity. Exact identification and locality cannot be confirmed from the photograph alone.

Field identification & locations

Look for strong resistance to scratching, opaque earthy color, waxy-to-glassy polish, and conchoidal chips; it commonly occurs in volcanic terrains worldwide, including Oregon, Idaho, Arizona, Madagascar, and Australia.