mineral

Quartz-rich river pebble (likely milky quartz or quartzite)

Quartz, SiO₂; possibly quartzite, a metamorphic rock dominated by quartz

AI-generated identification · may be incorrect

White to pale gray, translucent patches, vitreous to dull luster, irregular fracture, and no obvious cleavage; quartz hardness is Mohs 7, with specific gravity about 2.65.

Identified August 21, 2026More mineral →

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Physical properties

White to pale gray, translucent patches, vitreous to dull luster, irregular fracture, and no obvious cleavage; quartz hardness is Mohs 7, with specific gravity about 2.65.

Formation & geological history

Likely formed from silica-rich igneous or metamorphic material and rounded by stream or beach transport; its exact geological age cannot be determined from the photograph.

Uses & applications

Common quartz pebbles have little commercial value, though quartzite is used as aggregate, construction stone, and occasionally decorative stone; attractive pieces are collected or polished.

Geological facts

The visible pale, glassy appearance and rounded shape are consistent with quartz, but the image is insufficient to distinguish pure quartz from quartzite or another light-colored silicate rock.

Field identification & locations

Test for hardness by scratching glass; quartz should scratch it, while a steel knife generally will not scratch quartz. Common worldwide in stream gravels, beaches, and quartz veins.