mineral

Quartz

Silicon Dioxide (SiO2)

Mohs hardness of 7, white to clear color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture, specific gravity of 2.65

Identified July 29, 2026More mineral →

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Physical properties

Mohs hardness of 7, white to clear color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture, specific gravity of 2.65

Formation & geological history

Forms in a wide variety of geological environments, commonly crystallizing from silica-rich hydrothermal solutions, magma, and as a primary component of many igneous, metamorphic, and sedimentary rocks.

Uses & applications

Used in electronics, glassmaking, abrasives, gemstones, and decorative items.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust, surpassed only by feldspar. It exhibits piezoelectric properties, meaning it can generate an electric charge in response to applied mechanical stress.

Field identification & locations

Can be identified by its hardness (scratches glass), lack of cleavage, and typical conchoidal fracture. Found worldwide in nearly every geological setting.