mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glassy)

Identified April 1, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: 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 almost all geological environments and across all ages of Earth's history.

Uses & applications

Extensively used in electronics (oscillators), optics, watchmaking (piezoelectric properties), glassmaking, and widely as a gemstone or decorative specimen in jewelry.

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 pressure is applied.

Field identification & locations

Identify by its ability to scratch glass, lack of cleavage (it breaks in curved 'conchoidal' fractures), and six-sided crystal habit. Found globally, especially in pegmatites and mountain ranges like the Alps or Arkansas, USA.