mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/transparent; Luster: Vitreous; Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

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

Identified March 25, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/transparent; Luster: Vitreous; Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed from the cooling of silica-rich magma or through hydrothermal activity in veins. It can be found in a wide variety of igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & applications

Used in electronics for its piezoelectric properties (oscillators), glassmaking, abrasives, jewelry, and widely collected as metaphysical or decorative specimens.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the Greek word 'krustallos', meaning ice, as ancient Greeks believed it was ice that had frozen so hard it could never melt.

Field identification & locations

Identify in the field by its hexagonal crystal habit, lack of cleavage, and ability to scratch glass. Found globally, notably in Brazil, Arkansas (USA), and Madagascar. Collectors look for clarity and termination points.