mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, vitreous luster, conchoidal fracture, hexagonal crystal system, specific gravity of 2.65, often showing brownish to yellowish coloration due to iron oxide impurities.

Identified July 29, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, vitreous luster, conchoidal fracture, hexagonal crystal system, specific gravity of 2.65, often showing brownish to yellowish coloration due to iron oxide impurities.

Formation & geological history

Formed in a wide variety of geological environments including igneous, metamorphic, and sedimentary rocks, often precipitated from silica-rich hydrothermal solutions over millions of years.

Uses & applications

Used in electronics, watches, glassmaking, abrasive materials, and as gemstones or mineral specimens for collectors.

Geological facts

Quartz is one of the most abundant minerals in the Earth's continental crust and exhibits piezoelectric properties, meaning it can generate an electrical charge when mechanical stress is applied.

Field identification & locations

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