mineral

Tumbled jasper or chert

Microcrystalline quartz (SiO₂), likely iron-stained jasper

AI-generated identification · may be incorrect

Opaque tan-orange, earthy to waxy luster, fine-grained and apparently tumbled/rounded; quartz hardness is about 7 Mohs, with no visible cleavage and conchoidal fracture. Exact identification is limited by the image; it could also be a weathered chert or iron-rich chalcedony.

Identified August 26, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater replaces or fills cavities in sedimentary or volcanic rocks, with iron oxides producing the warm coloration. Formation age depends on locality and may range from Paleozoic to recent geological settings.

Uses & applications

Used as a lapidary material for cabochons, beads, carvings, and decorative objects; attractive jasper is collected rather than used structurally.

Geological facts

Jasper is an opaque variety of chalcedony or microcrystalline quartz, unlike translucent agate. The smooth shape suggests natural stream wear or human tumbling.

Field identification & locations

Common in silica-rich volcanic and sedimentary terrains worldwide, including the western United States, Madagascar, Brazil, and Australia. A glass-scratch test may support quartz hardness, but avoid damaging collectible material.