mineral

Tumbled quartz pebble (probable)

Quartz, silicon dioxide (SiO₂), possibly milky quartz or quartz-rich river stone

AI-generated identification · may be incorrect

Hardness 7 Mohs; pale gray-beige, translucent to opaque, with a dull-to-glassy luster and no obvious cleavage. The rounded shape and smooth surface indicate natural water wear or tumbling; microscopic inclusions or weathering may cause the cloudy appearance.

Identified September 21, 2026More mineral →

Explore Tumbled quartz pebble (probable) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Likely formed in an igneous or metamorphic host rock and later liberated by erosion, then rounded in a stream or by polishing. Quartz is common from Precambrian to modern environments, so age cannot be determined from the image.

Uses & applications

Used as aggregate, abrasives, glass and silicon feedstock; attractive pieces are collected or used in crafts and jewelry. This small specimen has mainly decorative value.

Geological facts

Quartz is one of Earth’s most abundant minerals and is chemically resistant, allowing it to survive transport as durable pebbles.

Field identification & locations

Confirm with a steel file or knife: quartz should resist scratching, though testing may mark the surface. Common worldwide in stream gravels, veins, granite, and metamorphic rocks; the image alone cannot exclude chalcedony or another hard silicate.