sedimentary
River Stone
Water-worn lithic fragment
Hardness varies by mineral composition (typically Mohs 6-7 for quartz-rich stones), color is grayish-brown, luster is dull to sub-vitreous, smooth and rounded crystal/granular structure due to weathering, no distinct cleavage planes visible externally.
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Physical properties
Hardness varies by mineral composition (typically Mohs 6-7 for quartz-rich stones), color is grayish-brown, luster is dull to sub-vitreous, smooth and rounded crystal/granular structure due to weathering, no distinct cleavage planes visible externally.
Formation & geological history
Formed through the natural weathering, erosion, and transport of parent rocks (such as granite, quartzite, or sandstone) along riverbeds and streams over thousands to millions of years.
Uses & applications
Used primarily in landscaping, decorative garden features, aquascaping, and construction aggregate.
Geological facts
The smooth and rounded shape of river stones is caused by mechanical weathering, where rocks tumble and collide with one another in flowing water, wearing away sharp edges.
Field identification & locations
Commonly found in and around riverbeds, ancient floodplains, and gravel bars worldwide. Easily identified by its smooth, water-worn surface and rounded contours.
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