sedimentary

Rounded quartz-rich pebble

Likely quartzite or quartz-rich sandstone; identification is uncertain from the photograph alone

AI-generated identification · may be incorrect

Pale tan, rounded, and granular with a dull-to-slightly-glassy surface. Quartz has Mohs hardness 7 and trigonal crystal structure; quartzite is typically hard and lacks prominent cleavage.

Identified October 10, 2026More sedimentary →

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Physical properties

Pale tan, rounded, and granular with a dull-to-slightly-glassy surface. Quartz has Mohs hardness 7 and trigonal crystal structure; quartzite is typically hard and lacks prominent cleavage.

Formation & geological history

Likely formed from quartz-rich sediment that was compacted and cemented, or from sandstone recrystallized into quartzite; river or beach transport rounded the pebble. Its age and exact formation cannot be determined visually.

Uses & applications

Primarily a decorative or collecting specimen; quartz-rich stone is also used as aggregate and, when suitable, building stone.

Geological facts

Quartz-rich rocks commonly resist weathering, helping them persist as smooth stream and beach pebbles.

Field identification & locations

A scratch test against glass can help assess hardness, while a fresh broken surface may reveal grains or interlocking quartz. Quartzite occurs worldwide; provenance cannot be inferred from appearance alone.