mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, vitreous to greasy luster, transparent to opaque, conchoidal fracture, lack of cleavage, specific gravity of 2.65, trigonal crystal system.

Identified August 2, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, vitreous to greasy luster, transparent to opaque, conchoidal fracture, lack of cleavage, specific gravity of 2.65, trigonal crystal system.

Formation & geological history

Forms in a wide variety of geological environments including igneous, metamorphic, and sedimentary rocks. It is a primary component of granite and sandstone, and often crystallizes from hydrothermal veins.

Uses & applications

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

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

Easily identified by its hardness (scratches glass), lack of cleavage, and distinct conchoidal fracture. Found worldwide in nearly every type of geological terrain.