mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

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

Identified May 30, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from cooling silica-rich magma or hydrothermal veins. Found in various geological ages and environments, primarily within igneous and metamorphic formations.

Uses & applications

Used in jewelry, electronics (oscillators), optics, glass making, and as a popular collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the Greek word 'krustallos', meaning ice.

Field identification & locations

Identify by its hardness (scratches glass), hexagonal crystal shape, and conchoidal fracture. Found worldwide, particularly in Brazil, Arkansas (USA), and the Alps.