mineral

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 (Mohs scale), Color: Milky white to translucent, Luster: Vitreous/Waxy, Crystal Structure: Hexagonal (though not visible in tumbled specimens), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified March 29, 2026More mineral →

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Physical properties

Formation & geological history

Formed from molten silica cooling in igneous rocks or precipitated from hydrothermal fluids. This specific specimen is a 'water-worn' pebble, meaning its rounded shape was created through mechanical weathering and erosion over thousands of years in a riverbed or coastal environment.

Uses & applications

Used in industry for glassmaking, abrasives, and electronics (due to piezoelectricity). In this pebble form, it is commonly used in decorative landscaping, aquarium gravel, or as pocket stones for hobbyist collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its cloudy appearance from microscopic inclusions of fluids or gas trapped within the crystal as it grows.

Field identification & locations

Identify in the field by its hardness (it will easily scratch glass and cannot be scratched by a steel knife) and lack of cleavage. It is found globally in riverbeds, beaches, and soil. Collectors look for clarity or embedded inclusions.