sedimentary
Pebble / Rounded Rock
Lithic fragment / Water-worn rock
AI-generated identification · may be incorrectHardness varies by mineral composition (typically 5 to 7 on the Mohs scale); Color ranges from brown, gray, to tan; Luster is dull to earthy; Texture is smooth due to water erosion.
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Physical properties
Hardness varies by mineral composition (typically 5 to 7 on the Mohs scale); Color ranges from brown, gray, to tan; Luster is dull to earthy; Texture is smooth due to water erosion.
Formation & geological history
Formed through the weathering and erosion of larger parent rocks, subsequently transported and rounded by water action in rivers, streams, or coastal environments over long periods.
Uses & applications
Used in landscaping, decorative paths, gardening, and occasionally as a tumbling or crafting material.
Geological facts
Water-worn pebbles like this undergo a process called rounding, where sharp edges and corners are worn away through continuous abrasion against other rocks in high-energy aquatic environments.
Field identification & locations
Commonly found in riverbeds, beaches, and glacial outwash plains. Easily identified by its smooth, rounded shape and lack of sharp angles.
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