mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White/Milky to translucent, Luster: Vitreous to waxy, Crystal structure: Trigonal/Hexagonal (though water-worn), Cleavage: None/Conchoidal fracture, Specific gravity: 2.65

Identified June 12, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as a primary constituent of igneous rocks. This specific specimen is a tumbled pebble, meaning it has been weathered and rounded by water transport in a river, stream, or coastal environment over thousands of years.

Uses & applications

Used as an abrasive, in glassmaking, as ornamental gravel in landscaping, and as a common collectible for beginner geologists and hobbyists. High-purity quartz is also essential in electronics.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. White or 'milky' quartz gets its opacity from tiny fluid inclusions of gas and liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (it should scratch glass and steel) and lack of cleavage. It is found globally in almost all geological settings, particularly in river beds and beaches.