mineral

Tumbled banded jasper, likely brecciated jasper

Microcrystalline quartz (SiO₂) with iron-oxide and clay inclusions

AI-generated identification · may be incorrect

Opaque reddish-purple and gray stone with a white vein or band; waxy to dull luster and conchoidal fracture. Quartz hardness is about 6.5–7 Mohs; crystal structure is cryptocrystalline, with no visible cleavage and typical specific gravity near 2.6.

Identified August 9, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids replace or cement volcanic or sedimentary material, commonly incorporating iron oxides that create red and purple colors; the white zone may be quartz or chalcedony filling a fracture. Its exact geological age cannot be determined from the photograph.

Uses & applications

Used for cabochons, beads, carvings, polished stones, and lapidary collections; occasionally used decoratively. Common tumbled pieces generally have modest commercial value.

Geological facts

Jasper is an opaque variety of chalcedony, unlike translucent agate. Color intensity commonly reflects hematite, goethite, or other iron-bearing minerals.

Field identification & locations

Identify it by its opaque fine-grained texture, red/gray patterning, hardness, and lack of obvious crystal faces; it should resist scratching by a steel knife. Similar material occurs worldwide, especially in volcanic terrains and silica-rich sedimentary deposits.