sedimentary
River Pebble
Polished Rock Fragment
AI-generated identification · may be incorrectHardness varies between 6-7 on the Mohs scale depending on mineral content; usually gray, brown, or multi-colored; dull to sub-vitreous luster; rounded and smooth due to water erosion.
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Physical properties
Hardness varies between 6-7 on the Mohs scale depending on mineral content; usually gray, brown, or multi-colored; dull to sub-vitreous luster; rounded and smooth due to water erosion.
Formation & geological history
Formed through the continuous water transport, erosion, and smoothing of larger rock fragments in rivers, streams, or beach environments over thousands to millions of years.
Uses & applications
Used in landscaping, gardening, decorative pathways, and occasionally in small crafts.
Geological facts
River pebbles are excellent indicators of ancient water flows and are commonly studied in geology to understand sedimentary transport processes.
Field identification & locations
Found globally in riverbeds, lake shores, and beaches. Identified by its smooth, water-worn shape and rounded edges.
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