sedimentary

Pea Gravel / River Gravel

Unconsolidated Clastic Sedimentary Aggregate

Hardness: Varies (5-7 on Mohs scale depending on clast composition like quartz, chert, granite); Color: Mixed shades of grey, tan, brown, white, and red; Luster: Dull to earthy; Texture: Rounded to sub-rounded pebbles; Size: 2mm to 64mm

Color: Mixed shades of grey, tan, brown, white, and red
Luster: Dull to earthy

Identified July 25, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the mechanical weathering, erosion, and transport of rocks by flowing river currents or glacial meltwater, which naturally rounds the fragment edges over time.

Uses & applications

Extensively used in construction, driveway surface material, aggregate for concrete and asphalt, landscaping decorative gravel, drainage systems, and walkway paving.

Geological facts

Pea gravel gets its name from its small, smooth size resembling natural peas. These deposits are typically harvested from ancient riverbeds, glacial moraines, or active alluvial floodplains.

Field identification & locations

Identified by a loose collection of small, rounded rock pebbles. Found abundantly worldwide along river valleys and quarry sites. Very low individual value, typically sold in bulk by the ton ($30-$60/ton).

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