sedimentary
River Pebble
Polished lithic fragment
AI-generated identification · may be incorrectHardness typically 6-7 on Mohs scale depending on mineral makeup; color ranges from gray to dark charcoal; luster is dull to sub-vitreous; amorphous smoothed crystal structure due to abrasion.
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Physical properties
Hardness typically 6-7 on Mohs scale depending on mineral makeup; color ranges from gray to dark charcoal; luster is dull to sub-vitreous; amorphous smoothed crystal structure due to abrasion.
Formation & geological history
Formed through the continuous water-borne erosion, weathering, and smoothing of parent rock fragments over thousands to millions of years in riverbeds or coastal environments.
Uses & applications
Used extensively in landscaping, decorative garden design, terrariums, and occasionally in artisanal crafts.
Geological facts
River pebbles become uniquely rounded and polished through a natural tumbling process called attrition as water carries them downstream.
Field identification & locations
Easily identified by its smooth, water-worn texture and rounded shape, commonly found along riverbanks, lake shores, and stream beds worldwide.
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