mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically white, clear, or milky in color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture, no true cleavage, specific gravity of 2.65.

Identified August 6, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, typically white, clear, or milky in color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture, no true cleavage, specific gravity of 2.65.

Formation & geological history

Forms in a wide variety of geological environments, most commonly as a primary mineral in igneous rocks like granite and pegmatites, in hydrothermal veins, and as detrital grains in sedimentary rocks due to its high resistance to weathering.

Uses & applications

Used in electronics (oscillator crystals), glassmaking, abrasives, gemstones, and construction materials.

Geological facts

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

Field identification & locations

Can be identified in the field by its high hardness (scratches glass easily), conchoidal fracture, and lack of cleavage. Found worldwide in almost every geological setting.