mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous

Identified May 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It occurs in almost all geological environments and across all geological ages, typically in granitic rocks and pegmatites.

Uses & applications

Used in electronics (oscillators), manufacturing of glass and ceramics, as gemstones in jewelry, and widely collected for metaphysical or decorative purposes.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is traditionally called rock crystal or clear quartz and was historically used to make 'crystal balls'.

Field identification & locations

Identify by its ability to scratch glass, its lack of cleavage, and its six-sided prismatic crystals. Common in mountain ranges like the Alps or the Arkansas Ouachita Mountains.