mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically white, clear, or milky with a vitreous to greasy luster, hexagonal crystal system, conchoidal fracture, specific gravity of 2.65.

Identified July 29, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, typically white, clear, or milky with a vitreous to greasy luster, hexagonal crystal system, conchoidal fracture, specific gravity of 2.65.

Formation & geological history

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

Uses & applications

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

Geological facts

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

Field identification & locations

Easily identifiable in the field by its high hardness (scratches glass), lack of cleavage, and typical conchoidal fracture. Found worldwide in nearly every geological setting.