sedimentary
River Pebble
Polished Rock Fragment
Hardness varies between 6-7 on the Mohs scale depending on mineral content; usually gray, brown, or multi-colored; dull to sub-vitreous luster; rounded and smooth due to water erosion.
Identified More sedimentary →
Explore River Pebble in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness varies between 6-7 on the Mohs scale depending on mineral content; usually gray, brown, or multi-colored; dull to sub-vitreous luster; rounded and smooth due to water erosion.
Formation & geological history
Formed through the continuous water transport, erosion, and smoothing of larger rock fragments in rivers, streams, or beach environments over thousands to millions of years.
Uses & applications
Used in landscaping, gardening, decorative pathways, and occasionally in small crafts.
Geological facts
River pebbles are excellent indicators of ancient water flows and are commonly studied in geology to understand sedimentary transport processes.
Field identification & locations
Found globally in riverbeds, lake shores, and beaches. Identified by its smooth, water-worn shape and rounded edges.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sedimentary Sandstone
Arenite (Sedimentary Rock)
sedimentary
Fossiliferous Concretion
Septarian Concretion containing Brachiopods/Crinoids
fossil
Banded Siltstone / Mudstone Pebble
Siltstone / Argillite
sedimentary
Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
sedimentary
Shale
Shale (clastic sedimentary rock)
sedimentary