mineral

Tumbled jasper (likely brecciated or red jasper)

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide inclusions

AI-generated identification · may be incorrect

Opaque, burgundy-red and dark gray/black mottling, glassy-to-waxy luster, and smoothly tumbled surfaces. Hardness about 6.5–7 Mohs; no visible cleavage; specific gravity roughly 2.55–2.70. Exact identification is limited because polishing obscures texture.

Identified September 12, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater fills cavities or replaces rock, with iron oxides producing red coloration; brecciation can create angular dark patches. Most jasper is geologically young relative to its host volcanic or sedimentary rocks, commonly formed during late alteration and silica deposition.

Uses & applications

Used for beads, cabochons, carvings, ornaments, and lapidary work; modest jewelry and collector value.

Geological facts

Jasper is a dense, opaque variety of chalcedony rather than a single mineral species. The dark patches may represent breccia fragments, manganese/iron oxides, or less commonly volcanic matrix.

Field identification & locations

Likely a commercial tumbled stone rather than an identifiable local outcrop specimen. Oregon and the broader Pacific Northwest contain abundant volcanic rocks, silica veins, and jasper sources; confirm with a streak test (white, not metallic), glass-scratch test, and close inspection for quartz-like translucency at thin edges.