sedimentary
River Rock
Mixed composition, often quartzite, sandstone, or basalt
AI-generated identification · may be incorrectHardness varies (often 6-7), brownish-gray color, smooth and tumbled appearance, weathered surface
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Physical properties
Hardness varies (often 6-7), brownish-gray color, smooth and tumbled appearance, weathered surface
Formation & geological history
Formed through mechanical weathering and water transport in rivers or streams
Uses & applications
Landscaping, decorative stone, construction aggregate
Geological facts
River rocks are shaped by constant tumbling in water over years, giving them their characteristic smooth, rounded look.
Field identification & locations
Found in riverbeds, streams, and glacial deposits. Identifiable by their smooth, rounded shape.
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