sedimentary
River Pebble (Quartz/Chert mix)
Silicon Dioxide (SiO2) with various inclusions
AI-generated identification · may be incorrectHardness: 7 (Mohs scale), Color: tan, white, and translucent brown, Luster: Dull to waxy, Crystal Structure: Cryptocrystalline to microcrystalline, Specific Gravity: 2.65
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Physical properties
Hardness: 7 (Mohs scale), Color: tan, white, and translucent brown, Luster: Dull to waxy, Crystal Structure: Cryptocrystalline to microcrystalline, Specific Gravity: 2.65
Formation & geological history
Formed through the accumulation of silica-rich sediment in aqueous environments, often rounded by water erosion in rivers or coastal areas over thousands of years.
Uses & applications
Used primarily in landscaping, construction aggregate, and as decorative stone in gardens or aquariums.
Geological facts
These smooth, rounded stones are often referred to as 'alluvial deposits.' They can travel hundreds of miles from their original source through river transport.
Field identification & locations
Identify by their rounded shape, hardness (cannot be scratched by a steel blade), and smooth texture. Common in riverbeds, glacial deposits, and beaches.
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