Mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to milky white (opaque); Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal (though rounded by water); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to milky white (opaque)
Luster: Vitreous to waxy

Identified March 18, 2026More mineral →

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Physical properties

Formation & geological history

Formed from cooling magma or precipitation in hydrothermal veins. This specific specimen has been chemically and physically weathered and transported by water (fluvial or beach action) over thousands of years, resulting in its smooth, rounded 'pebble' shape.

Uses & applications

Common industrial use in glassmaking, abrasives, and as a component in concrete. Tumbled specimens are used in jewelry, landscaping, and as pocket stones for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Because of its high hardness and chemical stability, it survives the weathering process much longer than other minerals, which is why most beach sand is composed of quartz.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage planes, and its characteristic waxy luster. Commonly found in riverbeds, beaches, and glacial till worldwide.