sedimentary

Likely reddish-brown chert or jasper fragment

Microcrystalline quartz (SiO₂), possibly iron-oxide-bearing jasper

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; opaque reddish-brown with darker streaks, dull to slightly waxy luster, and conchoidal-looking fracture. Individual crystals are microscopic, so cleavage is absent; specific gravity is approximately 2.6.

Identified August 15, 2026More sedimentary →

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Physical properties

Formation & geological history

Forms when silica-rich fluids replace or cement sediment, with iron oxides producing the red-brown color; it may range from Paleozoic to younger in age depending on locality. The irregular shape appears naturally broken or roughly knapped, though the image alone cannot confirm this.

Uses & applications

Used as aggregate, road material, abrasives, and occasionally ornamental stone or lapidary material. Attractive jasper can be polished for cabochons and carvings.

Geological facts

Chert and jasper are varieties of microcrystalline quartz; jasper is typically opaque and strongly colored by impurities. Exact identification requires a sharper view and tests such as streak, hardness, and specific gravity.

Field identification & locations

Look for glassy/conchoidal fracture, inability to scratch with a steel knife, and white-to-colorless streak; it should not fizz with dilute hydrochloric acid. Common in sedimentary formations worldwide, including the United States, Australia, and India.