sedimentary

Rounded river pebble

Indeterminate lithic clast; likely weathered sandstone or quartz-rich sedimentary rock

AI-generated identification · may be incorrect

Small, smooth, tan-gray, opaque pebble with dull earthy luster and faint mottling. Estimated hardness 5–7 Mohs; granular texture and lack of visible crystals suggest a sedimentary clast, though the image is insufficient for confident mineral identification.

Identified August 13, 2026More sedimentary →

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Physical properties

Formation & geological history

Rounded by abrasion in a stream, river, or beach environment; its original rock may be much older than the modern deposit. Exact age and formation cannot be determined visually.

Uses & applications

Primarily a natural collectible or landscaping/decorative stone; no significant industrial or jewelry value is apparent.

Geological facts

The smooth shape records prolonged transport and repeated impacts. A streak, hardness test, and fresh broken surface would help distinguish sandstone from quartzite, chert, or weathered igneous rock.

Field identification & locations

Common in stream gravels worldwide. Look for grain visibility, reaction to dilute hydrochloric acid, and whether it scratches glass; avoid destructive tests if it is a valued find.