mineral

Clear Quartz

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 18, 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 from cooling magma (igneous) or precipitation from hydrothermal veins. Found globally in almost every geological environment.

Uses & applications

Used in jewelry, timekeeping (piezoelectric properties), glassmaking, electronics, and as a popular collector specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is traditionally called rock crystal.

Field identification & locations

Identify by its hardness (will scratch glass), hexagonal crystal habit, and conchoidal (glass-like) fracture pattern. Found in Arkansas (USA), Brazil, and Madagascar.