mineral

Tumbled brown stone, likely brown jasper or iron-rich chert

Microcrystalline quartz (SiO₂), possibly hematite/goethite-bearing

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; opaque reddish-brown to dark brown, with a smooth tumbled surface and dull to waxy luster. Quartz is trigonal and has no cleavage; the visible metallic-looking speckles may be iron oxides.

Identified September 7, 2026More mineral →

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Physical properties

Formation & geological history

Likely formed by silica replacement or cementation in sedimentary environments, with iron staining during weathering; exact age and locality cannot be determined from the photograph.

Uses & applications

Used as a decorative tumbled stone, cabochon, pendant, or low-cost lapidary material; not generally used as a major construction stone in this form.

Geological facts

Brown jasper and chert can look nearly identical in photographs; a conclusive identification requires hardness, streak, translucency, and possibly specific-gravity testing.

Field identification & locations

Common in many silica- and iron-rich regions worldwide. It should scratch glass but not be scratched by a steel knife; a white streak and conchoidal fracture support chert/jasper, while strong magnetism would suggest magnetite-bearing material.