mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Colorless to white/cloudy; Luster: Vitreous (glassy); Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Colorless to white/cloudy
Luster: Vitreous (glassy)

Identified April 3, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Colorless to white/cloudy; Luster: Vitreous (glassy); Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in a variety of environments from cooling magma (igneous), hydrothermal veins, or through sedimentary and metamorphic processes. Occurs in rocks of all geological ages.

Uses & applications

Used in electronics for its piezoelectric properties, glassmaking, construction sand, watch movements, and as a gemstone/ornamental stone in jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It was historically called 'rock crystal' and was once believed to be permanently frozen ice by ancient philosophers.

Field identification & locations

Identify by its hardness (scratches glass/steel), lack of cleavage, and the way it breaks into curved 'conchoidal' surfaces. Commonly found in mountains, riverbeds, and beaches.