sedimentary
Pebble
Lithified rock fragment
AI-generated identification · may be incorrectHardness varies by mineral composition (typically Mohs 6-7 for quartz-rich pebbles); rounded shape with smooth or weathered texture; various colors.
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Physical properties
Hardness varies by mineral composition (typically Mohs 6-7 for quartz-rich pebbles); rounded shape with smooth or weathered texture; various colors.
Formation & geological history
Formed through the weathering and mechanical erosion of larger rock masses, followed by water or wind transport that smooths the edges in riverbeds or coastal environments.
Uses & applications
Used in landscaping, decorative pathways, construction aggregate, and by rock collectors.
Geological facts
Pebbles are classified by size on the Wentworth scale, ranging from 4 to 64 millimeters in diameter. Their rounding indicates the distance and energy of transport.
Field identification & locations
Found abundantly in streambeds, beaches, and glacial till; identified by smooth, water-worn shapes and resistance to weathering.
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