mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glass-like)

Identified March 14, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It can be found in igneous, metamorphic, and sedimentary environments across all geological ages, often growing in cavities or geodes.

Uses & applications

Used widely in electronics (oscillators), glassmaking, abrasives, and as semi-precious gemstones in jewelry. Highly valued in the metaphysical and specimen collecting communities.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, the Greeks believed clear quartz was 'ice that had frozen so hard it would never melt,' hence the name 'krystallos'.

Field identification & locations

Identify by its ability to scratch glass, its six-sided prismatic shape with pyramidal terminations, and the lack of cleavage. Common worldwide, with high-quality deposits in Brazil, Arkansas (USA), and Madagascar.