mineral

Polished brown gemstone, likely jasper or bronzite

Jasper: microcrystalline SiO₂; possible bronzite: (Mg,Fe)SiO₃

AI-generated identification · may be incorrect

Small tumbled/polished, opaque brown stone with subtle metallic or granular speckling and a glossy luster. Likely hardness about 5.5–7 Mohs; exact identification requires testing because the image lacks diagnostic detail.

Identified August 26, 2026More mineral →

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Physical properties

Formation & geological history

If jasper, it formed from silica-rich fluids replacing or cementing volcanic or sedimentary material, commonly in Precambrian to younger rocks; bronzite forms in metamorphic or igneous ultramafic rocks. Geological age cannot be determined from the photograph.

Uses & applications

Used as a lapidary, tumbled stone, cabochon, or decorative collectible; jasper is also used for carvings and ornamental objects.

Geological facts

The white surface appears to be a countertop rather than part of the specimen. A hardness test, streak, and close inspection of texture would distinguish jasper from bronzite, mahogany obsidian, or other brown stones.

Field identification & locations

Jasper typically shows opaque, earthy patterns and leaves no streak on unglazed porcelain; bronzite commonly has a bronze flash and visible cleavage. Common sources include India, Brazil, Madagascar, Australia, and the United States.