mineral

Quartz

Silicon Dioxide (SiO2)

Hardness 7 on Mohs scale, milky white to translucent color, vitreous to greasy luster, trigonal crystal structure, conchoidal fracture, lacks true cleavage, specific gravity ~2.65.

Identified July 24, 2026More mineral →

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Physical properties

Hardness 7 on Mohs scale, milky white to translucent color, vitreous to greasy luster, trigonal crystal structure, conchoidal fracture, lacks true cleavage, specific gravity ~2.65.

Formation & geological history

Forms in a wide variety of geological environments including igneous, metamorphic, and sedimentary settings. Commonly crystallizes from cooling magma or precipitates from hydrothermal fluids.

Uses & applications

Used extensively in electronics (piezoelectric oscillators), glass manufacturing, abrasives, construction aggregates, gemology, and ornamental carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to both chemical weathering and physical breakdown.

Field identification & locations

Identified in the field by its hardness (scratches glass), glass-like to greasy luster, and lack of cleavage. Found virtually everywhere on Earth in riverbeds, mountains, beaches, and gravel paths.