mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs), Color: Colorless/Transparent, Luster: Vitreous, Crystal System: Trigonal (hexagonal prism), Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Identified May 9, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs), Color: Colorless/Transparent, Luster: Vitreous, Crystal System: Trigonal (hexagonal prism), Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or hydrothermal solutions in rock cavities. Found in all types of geological environments (igneous, metamorphic, and sedimentary) across all geological ages.

Uses & applications

Used in electronics for its piezoelectric properties, glassmaking, jewelry, sandpaper, and as a popular collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It was historically believed by the Greeks to be ice that was permanently frozen because it was found in glaciers.

Field identification & locations

Identify by its hexagonal point shape, lack of cleavage, and ability to scratch glass. Found globally, with notable deposits in Brazil, Arkansas (USA), and Madagascar.