sedimentary
River Rock
Siliceous rock fragment
AI-generated identification · may be incorrectHardness 7 on Mohs scale, brown to reddish color, dull to waxy luster, amorphous crystal structure, no distinct cleavage, specific gravity around 2.65.
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Physical properties
Hardness 7 on Mohs scale, brown to reddish color, dull to waxy luster, amorphous crystal structure, no distinct cleavage, specific gravity around 2.65.
Formation & geological history
Formed through mechanical weathering and prolonged water transport in riverbeds, rounding sharp edges over millions of years.
Uses & applications
Commonly used in landscaping, garden decoration, pathways, and construction aggregate.
Geological facts
River rocks are continuously shaped by hydraulic action and abrasion as they collide with other rocks in fast-flowing water.
Field identification & locations
Identified by its smooth, rounded shape and resistance to scratching. Easily found in active or dry riverbeds worldwide.
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