Rock Identifier
Quartz Pebble (Silicon dioxide (SiO2)) — sedimentary
sedimentary

Quartz Pebble

Silicon dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically rounded or smooth due to water transport, vitreous luster on fractured surfaces, conchoidal fracture, and specific gravity of around 2.65.

Identified More sedimentary
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Physical properties

Hardness of 7 on the Mohs scale, typically rounded or smooth due to water transport, vitreous luster on fractured surfaces, conchoidal fracture, and specific gravity of around 2.65.

Formation & geological history

Formed through the mechanical weathering and long-term aqueous transport of primary quartz-bearing rocks like granite or vein quartz, where softer minerals are worn away, leaving highly durable quartz pebbles.

Uses & applications

Used in landscaping, decorative stone, aggregate in construction, and occasionally in lapidary arts for tumbling and polishing.

Geological facts

Quartz is one of the most abundant and durable minerals in Earth's continental crust, which is why quartz pebbles are ubiquitous in riverbeds and beaches worldwide.

Field identification & locations

Easily identified by its high hardness (scratches glass), lack of cleavage, and smooth water-worn shape found abundantly in gravel bars, riverbeds, and sedimentary conglomerates.