sedimentary
River Gravel
Polymictic pebble conglomerate / alluvial gravel
AI-generated identification · may be incorrectHardness varies by mineral content (Mohs 6-7 mostly quartz); colors range from white and gray to tan and reddish-brown; smooth, rounded luster; variable crystal structure.
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Physical properties
Hardness varies by mineral content (Mohs 6-7 mostly quartz); colors range from white and gray to tan and reddish-brown; smooth, rounded luster; variable crystal structure.
Formation & geological history
Formed through the mechanical weathering, erosion, and long-term water transport of various parent rocks in riverbeds and glacial outwash.
Uses & applications
Widely used in landscaping, drainage systems, concrete aggregate, and pathway construction.
Geological facts
The rounded shape results from continuous tumbling and abrasion against other rocks during river transport over miles.
Field identification & locations
Easily identified by smooth, rounded surfaces and mixed mineral composition found along waterways or landscaping beds; popular for bulk landscaping.
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