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 25, 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 in igneous, metamorphic, and sedimentary environments through the cooling of silica-rich magma or from hydrothermal solutions. It can be found in variety of geological ages from Precambrian to recent.

Uses & applications

Extensively used in electronics (oscillators), optics, glassmaking, and jewelry. It is also highly valued in specimen collecting and various metaphysical practices.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, the word 'crystal' comes from the Greek word 'krystallos,' which means ice, as ancient Greeks believed quartz was permanently frozen ice.

Field identification & locations

Identify by its ability to scratch glass and lack of cleavage. In the field, look for hexagonal prism shapes and horizontal striations on crystal faces. Found globally, especially in granite pegmatites and hydrothermal veins.