mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale, Color: Colorless (Clear), Luster: Vitreous (glassy), Crystal Structure: Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified August 3, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale, Color: Colorless (Clear), Luster: Vitreous (glassy), Crystal Structure: Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Forms from silicon and oxygen rich fluids in hydrothermal veins, pegmatites, and igneous, metamorphic, and sedimentary rocks over millions of years.

Uses & applications

Used in electronics, watches, glassmaking, abrasive materials, jewelry, and crystal healing.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It exhibits piezoelectric properties, meaning it can generate an electrical charge in response to mechanical stress.

Field identification & locations

Identified by its hexagonal crystal habit, lack of cleavage, glass luster, and hardness sufficient to scratch glass. Found worldwide, with notable deposits in Brazil, the USA, and the Alps.