sedimentary
River Pebbles
Polymictic Gravel
AI-generated identification · may be incorrectHardness varies (6-7 Mohs), diverse multicolored quartz, basalt, and quartzite composition, smooth rounded luster.
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Physical properties
Hardness varies (6-7 Mohs), diverse multicolored quartz, basalt, and quartzite composition, smooth rounded luster.
Formation & geological history
Formed through the continuous water-driven erosion and abrasion of various parent rocks along riverbeds over millennia.
Uses & applications
Widely used in landscaping, garden pathways, drainage control, and decorative aggregate.
Geological facts
The smooth, rounded shapes are the result of physical tumbling against other rocks in high-energy water currents.
Field identification & locations
Identified by smooth, water-worn surfaces and mixed mineralogy; found globally in stream beds and ancient alluvial deposits.
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