mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Colorless/Transparent; Luster: Vitreous; Crystal Structure: Trigonal (hexagonal prisms); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

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

Identified July 3, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Colorless/Transparent; Luster: Vitreous; Crystal Structure: Trigonal (hexagonal prisms); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich magma or precipitation from hydrothermal veins. Occurs in nearly all geological environments (igneous, metamorphic, and sedimentary) across all geological ages.

Uses & applications

Used in electronics (oscillators), optical instruments, glass manufacturing, abrasives, jewelry, and metaphysical collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it generates an electric charge in response to applied mechanical stress.

Field identification & locations

Identify by its hardness (scratches glass), glass-like luster, and lack of cleavage. Found globally; major sources include Brazil, Arkansas (USA), and Madagascar. Look for six-sided crystals or irregular glassy fragments in gravel or vein outcrops.