sedimentary

Jasper (likely red jasper or brecciated chert)

Microcrystalline quartz/chalcedony, SiO₂, colored mainly by iron oxides

AI-generated identification · may be incorrect

Opaque reddish-brown, matte to waxy luster, very fine-grained with conchoidal fractures and an apparently knapped edge. Mohs hardness about 6.5–7; no cleavage; specific gravity roughly 2.5–2.7.

Identified September 3, 2026More sedimentary →

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Physical properties

Opaque reddish-brown, matte to waxy luster, very fine-grained with conchoidal fractures and an apparently knapped edge. Mohs hardness about 6.5–7; no cleavage; specific gravity roughly 2.5–2.7.

Formation & geological history

Forms when silica-rich fluids replace or cement sediments, often incorporating iron oxides that produce red or brown colors. It commonly formed in ancient volcanic-sedimentary environments from Precambrian through younger geologic ages.

Uses & applications

Used for beads, carvings, cabochons, and lapidary specimens; historically valuable for tools and projectile points because it fractures sharply.

Geological facts

The piece appears intentionally flaked or shaped, possibly a small stone-tool fragment rather than a naturally broken chip. Jasper grades continuously into chert and chalcedony.

Field identification & locations

Identify it by its opaque red color, uniform cryptocrystalline texture, hardness, and conchoidal fracture; it commonly occurs in iron-rich beds and silica-rich gravels worldwide, including the western United States, India, Brazil, and Australia.