sedimentary
Pebble
Lithified clastic rock fragment / Quartz-rich pebble
Hardness varies from 6 to 7 on the Mohs scale depending on mineral content; usually gray, brown, or multicolored; dull to sub-vitreous luster; smooth, rounded shape due to water or wind erosion.
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Physical properties
Hardness varies from 6 to 7 on the Mohs scale depending on mineral content; usually gray, brown, or multicolored; dull to sub-vitreous luster; smooth, rounded shape due to water or wind erosion.
Formation & geological history
Formed through the physical weathering and erosion of larger parent rocks, followed by the transport and rounding of fragments by water in rivers, streams, or ocean waves over thousands to millions of years.
Uses & applications
Used in landscaping, gardening, concrete aggregate, pathways, and decorative aquarium substrates.
Geological facts
Pebbles are scientifically classified based on their size, typically ranging from 4 to 64 millimeters in diameter according to the Krumbein phi scale.
Field identification & locations
Found abundantly along riverbeds, beaches, and ancient alluvial deposits; easily identified by its smooth, water-worn texture and small size.
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