mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/None; Specific Gravity: 2.65

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

Identified June 21, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/None; Specific Gravity: 2.65

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments, most commonly from the cooling of silica-rich magma or precipitation from hydrothermal veins. It can be found in rocks from all geological ages.

Uses & applications

Used in electronics (oscillators), glassmaking, precision instruments, jewelry, and as a popular decorative or healing stone in the metaphysical community.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. When clear and well-formed, it is known as Rock Crystal, a term derived from the Greek word 'krustallos' meaning ice.

Field identification & locations

Identify by its hardness (scratches glass), hexagonal crystal habit with horizontal striations on faces, and conchoidal (shell-like) fracture. Found globally, notably in Brazil, Arkansas (USA), and the Alps.