mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear to milky white; Luster: Vitreous (glassy); Crystal System: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear to milky white
Luster: Vitreous (glassy)

Identified June 2, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear to milky white; Luster: Vitreous (glassy); Crystal System: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of environments, most commonly by the cooling and crystallization of silica-rich magma or from hydrothermal veins. It is a major constituent of granite and many sedimentary rocks and can be found across all geological ages.

Uses & applications

Used extensively in glass manufacturing, electronics (due to piezoelectric properties), construction as an abrasive, and as a gemstone in jewelry and watches.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It was historically believed to be permanently frozen ice by ancient Greeks.

Field identification & locations

Identified in the field by its hardness (it can scratch glass), its glassy luster, and the lack of cleavage planes. It is found globally in many different rock types and riverbeds.