mineral

Rough Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Colorless to brownish/gray (Smoky variety); Luster: Vitreous (glassy); Crystal structure: Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Colorless to brownish/gray (Smoky variety)
Luster: Vitreous (glassy)

Identified March 16, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Colorless to brownish/gray (Smoky variety); Luster: Vitreous (glassy); Crystal structure: Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed through the cooling of magma (igneous) or precipitation from hydrothermal veins. It is found in rocks from all geological ages and can form in high-pressure metamorphic environments.

Uses & applications

Used in electronics (oscillators), glass manufacturing, abrasives, jewelry (gemstone quality), and as a common high-utility industrial aggregate in construction.

Geological facts

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

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (7 hardness) and its lack of cleavage (it breaks in curved, shell-like patterns). Commonly found in granite outcrops or as sand/pebbles in riverbeds worldwide.