mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Milky white to translucent; Luster: Vitreous to greasy (when weathered); Crystal structure: Trigonal/Hexagonal (though not visibly crystalline in this tumbled form); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Milky white to translucent
Luster: Vitreous to greasy (when weathered)

Identified March 22, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling and crystallization of silica-rich magma or from hydrothermal veins. This specific specimen has been chemically or mechanically weathered and rounded into a pebble by water transport (fluvial or beach processes) over thousands of years.

Uses & applications

Common quartz is used in the manufacture of glass, ceramics, and electronics. Tumbled pebbles like this are often used in landscaping, decorative gravel, and aquarium substrate.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. It is highly resistant to chemical and physical weathering, which is why it often remains as pebbles long after other minerals have decomposed into clay.

Field identification & locations

Identify in the field by its inability to be scratched by a steel pocket knife and its lack of reaction to acid. It is found globally in riverbeds, beaches, and glacial deposits. For collectors, look for unique inclusions or high clarity.