mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically white or colorless, vitreous luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified July 30, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, typically white or colorless, vitreous luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

Forms in a wide variety of geological environments including igneous, metamorphic, and sedimentary rocks. It is a major constituent of granites, pegmatites, and sandstones, crystallizing from silica-rich hydrothermal solutions or cooling magma.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasives, gemstones, and ornamental carvings.

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 electrical charge in response to applied mechanical stress.

Field identification & locations

Can be identified by its characteristic 7 Mohs hardness (scratches glass easily), conchoidal fracture, and lack of cleavage. Found worldwide in nearly every geological setting.