mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Colorless and transparent. Luster: Vitreous (glass-like). Crystal structure: Hexagonal/Trigonal. Cleavage: None, exhibits conchoidal fracture. Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Colorless and transparent
Luster: Vitreous (glass-like)

Identified July 22, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of geological environments including igneous pegmatites, hydrothermal veins, metamorphic rocks, and sedimentary deposits through the crystallization of silica-rich fluids.

Uses & applications

Widely used in jewelry, gemstone carving, optics, electronics (due to its piezoelectric properties), and popular among rock collectors and healing crystal enthusiasts.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure clear quartz was historically believed by ancient Greeks to be permanently frozen ice (krystallos) that would never melt.

Field identification & locations

Identified by its glass-like transparency, hardness of 7 (scratches glass and steel), and lack of true cleavage. Commonly found worldwide in riverbeds, pegmatite veins, and geodes in places like Brazil, Madagascar, Arkansas (USA), and the Alps.