mineral

Tumbled jasper or iron-rich chert

Microcrystalline quartz (SiO₂) with iron-oxide inclusions

AI-generated identification · may be incorrect

Typically Mohs hardness 6.5–7, opaque, with a waxy to dull luster and tan, brown, black, or red coloration from hematite/goethite. The specimen appears polished or naturally smoothed and lacks visible cleavage; exact identification is limited by the image.

Identified August 22, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids replace or cement sediments, with iron oxides producing the mottled patterns; formation ages vary widely, commonly Paleozoic to Mesozoic in sedimentary settings. Common sources include India, Madagascar, Brazil, Mexico, and the western United States.

Uses & applications

Used for cabochons, beads, carvings, tumbling, and decorative objects; crushed jasper/chert may serve as aggregate or silica material.

Geological facts

Jasper is a variety of opaque chalcedony, and its patterns are caused by mineral impurities rather than separate large crystals. A glassy conchoidal fracture and resistance to scratching are characteristic.

Field identification & locations

Look for dense, opaque material, conchoidal fracture, and inability to scratch it with a steel knife; it should scratch glass if quartz-rich. The visible fabric and scale suggest a small polished or naturally worn piece rather than an in-place rock.