mineral

Tumbled jasper or altered chalcedony

Microcrystalline quartz (SiO₂), possibly jasper/chalcedony

AI-generated identification · may be incorrect

Opaque to slightly translucent gray-green, cream, and brown material with a dull-to-waxy luster and irregular internal patterning. Quartz hardness is about 7 Mohs; no visible cleavage, and specific gravity is approximately 2.6.

Identified August 24, 2026More mineral →

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Physical properties

Formation & geological history

Likely silica-rich material formed when groundwater deposited microcrystalline quartz in cavities or replaced volcanic or sedimentary rock; the specimen appears naturally worn or lightly polished. Exact age and locality cannot be determined from the photograph.

Uses & applications

Commonly used for cabochons, beads, carvings, and inexpensive ornamental stones; rough pieces are mainly collector specimens. Typical value is low unless pattern, color, or locality is exceptional.

Geological facts

Jasper is opaque and commonly colored by iron or other impurities, while chalcedony is generally more translucent; many specimens grade between the two. The image alone cannot reliably distinguish this from several altered silicate rocks.

Field identification & locations

Field identification requires a scratch test: quartz should scratch ordinary glass, while a steel knife should not scratch it; inspect for waxy luster and conchoidal fracture. Similar-looking serpentine, nephrite, or weathered rock would require hardness, streak, and locality tests.