mineral

Jasper pebble, likely brecciated jasper

Microcrystalline quartz (SiO₂), commonly with iron-oxide impurities

AI-generated identification · may be incorrect

Opaque reddish-brown with gray and black patches, earthy to dull luster, and irregular fracture; quartz hardness is about 6.5–7 Mohs, with no cleavage. The visible dark gray material may be associated volcanic matrix or breccia fragments.

Identified August 20, 2026More mineral →

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Physical properties

Formation & geological history

Jasper forms when silica-rich fluids replace or cement volcanic, sedimentary, or hydrothermal rocks, with iron oxides producing the red coloration. Its exact geological age and locality cannot be determined from the photograph.

Uses & applications

Used for ornamental stone, cabochons, beads, carvings, and polished specimens; suitable pieces are collected as lapidary material rather than used structurally.

Geological facts

Jasper is a variety of opaque chalcedony or microcrystalline quartz, and color patterns commonly result from hematite, goethite, manganese oxides, or contrasting breccia fragments.

Field identification & locations

Identify it by its opacity, red iron-rich coloration, waxy-to-dull surface, and inability to scratch easily with a steel knife; a streak, hardness, and acid test can help distinguish it from softer iron-rich rocks. Common worldwide, especially in volcanic terrains.