mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: tan to creamy white, Luster: vitreous to waxy, Crystal structure: Hexagonal/Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified June 3, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: tan to creamy white, Luster: vitreous to waxy, Crystal structure: Hexagonal/Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of magma or precipitation from hydrothermal veins. This specific specimen is a water-worn pebble likely eroded from its parent rock and smoothed by fluvial or alluvial transport over thousands of years.

Uses & applications

Used in glassmaking, electronics, abrasives, and construction aggregate. Large specimens are popular for rock tumbling and as decorative garden stones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is chemically and physically resistant to weathering, which is why it often survives as small pebbles in riverbeds and on beaches.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife and its lack of cleavage. Look for smooth, rounded shapes in streambeds, gravel pits, and shoreline deposits.