Mixed (predominantly sedimentary and igneous)

River Pebbles (Stream-rounded rocks)

Fluvial Detritus (varied mineralogy)

AI-generated identification · may be incorrect

Hardness: 5-7 (Mohs scale), Color: shades of grey, tan, and muted pink, Luster: dull to earthy (waxy if wet), Structure: clastic or crystalline depending on specific pebble, Shapes: sub-rounded to rounded with smooth surfaces.

Identified March 15, 2026More mixed (predominantly sedimentary and igneous) →

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Physical properties

Formation & geological history

Formed through mechanical weathering and fluvial erosion. These are small fragments of larger rock formations (like granite, sandstone, or limestone) that have been transported by moving water, smoothing the edges over thousands of years.

Uses & applications

Commonly used in landscaping, decorative stone, construction aggregate, and gravel paths. High-quality smooth stones are also used in spa therapy (hot stones).

Geological facts

The roundness of these stones is a direct indicator of the energy of the water that transported them and the distance they traveled; the smoother the stone, the longer the journey.

Field identification & locations

Identify in the field by their smooth, rounded edges and lack of sharp fractures, usually found in riverbeds, glacial deposits, or beaches. Collectors value them for rock tumbling or decorative garden fillers.