mineral

Quartz-rich rock fragment

Microcrystalline quartz (SiO₂), possibly chalcedony or quartz-bearing breccia

AI-generated identification · may be incorrect

Gray-brown, translucent to opaque, with a dull-to-glassy luster and irregular granular texture. Quartz has Mohs hardness 7, no cleavage, conchoidal fracture, and specific gravity about 2.65; the specimen may include darker matrix minerals or iron staining.

Identified August 10, 2026More mineral →

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Physical properties

Formation & geological history

Likely formed when silica-rich fluids filled fractures or cavities and crystallized, potentially in volcanic or hydrothermal settings. The exact geological age and locality cannot be determined from the photograph.

Uses & applications

Common quartz-rich material is used for aggregate, glass, ceramics, and countertops; attractive pieces may be collected as lapidary specimens. This small, rough fragment has little commercial value.

Geological facts

Its translucent patches and glassy fracture are consistent with quartz or chalcedony, but the blurred image prevents confident identification of associated minerals.

Field identification & locations

Test with a steel file or quartz point: true quartz should resist scratching by steel. Common sources include hydrothermal veins, volcanic rocks, and weathered quartz gravels; estimated value is about $1–$10 as an ordinary specimen, potentially higher if confirmed as an unusual mineral.anges.