sedimentary

Red-brown jasper or iron-rich chert

Microcrystalline quartz (SiO₂), commonly colored by hematite/goethite

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; opaque reddish-brown with darker gray-blue patches, dull to weakly waxy luster, and no visible cleavage. The rounded, rough surface suggests a naturally weathered or tumbled microcrystalline-quartz pebble.

Identified August 26, 2026More sedimentary →

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Physical properties

Formation & geological history

Likely formed as silica-rich sediment or chemically deposited chert, later stained by iron oxides during weathering; exact geological age and locality cannot be determined from the photograph.

Uses & applications

Used as lapidary material, cabochons, carvings, beads, and ornamental stone; small common pieces have primarily educational or decorative value.

Geological facts

Jasper is an opaque variety of chalcedony/chert, and its red coloration commonly comes from finely disseminated hematite. Blue-gray areas may reflect other minerals or surface staining.

Field identification & locations

Confirm with a steel or glass scratch test, noting that true jasper should resist steel and may scratch glass; a streak test is usually pale or colorless rather than red. Commonly found in volcanic, sedimentary, and gravel deposits worldwide.