sedimentary
Pebble
Lithic fragment / Quartzite pebble
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, gray color, dull to vitreous luster, amorphous crystal structure, no cleavage, specific gravity of approximately 2.65.
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Physical properties
Hardness of 7 on the Mohs scale, gray color, dull to vitreous luster, amorphous crystal structure, no cleavage, specific gravity of approximately 2.65.
Formation & geological history
Formed through the mechanical weathering, transportation, and aqueous abrasion of parent rock over thousands to millions of years in riverbeds or coastal environments.
Uses & applications
Used in landscaping, construction aggregate, and as a common element in decorative gravel.
Geological facts
Pebbles are officially classified by geologists based on size, specifically ranging from 4 to 64 millimeters in diameter. Their smooth, rounded shape is the result of continuous tumbling and erosion by water.
Field identification & locations
Identified in the field by its smooth, water-worn exterior and typically found in stream beds, beaches, and glacial till deposits.
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