
sedimentary
River Rock
Silica-rich water-worn rock / Quartzite
AI-generated identification · may be incorrectHardness: 7 on Mohs scale (if quartzite); Color: brownish-gray; Luster: dull to vitreous; Structure: massive, rounded by water abrasion; Cleavage: none due to tumbling.
- Hardness
- 7 on Mohs scale (if quartzite)
- Color
- brownish-gray
- Luster
- dull to vitreous
Identified More sedimentary →
Explore River Rock in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 on Mohs scale (if quartzite); Color: brownish-gray; Luster: dull to vitreous; Structure: massive, rounded by water abrasion; Cleavage: none due to tumbling.
Formation & geological history
Formed through prolonged water transport and mechanical weathering in riverbeds and streams, smoothing angular rock fragments over thousands to millions of years.
Uses & applications
Landscaping, garden decoration, aquarium substrates, construction aggregate, and pathway paving.
Geological facts
Water-worn stones have been used by humans since prehistoric times for tools, cooking stones, and ornamentation due to their smooth, comfortable shapes.
Field identification & locations
Found abundantly in and along riverbeds, streams, and ancient glacial deposits worldwide. Easily identified by its smooth, rounded edges and water-worn exterior.
More like this
Other sedimentary specimens
Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
fossil
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite
sedimentary
Quartz pebble
Silicon dioxide (SiO2)
sedimentary
Shale
Shale (clastic sedimentary rock)
sedimentary
Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
sedimentary