mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

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

Identified June 21, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments through the cooling of magma or hydrothermal activity. It is found in all geological ages.

Uses & applications

Used in electronics (oscillators), glassmaking, gemstones, abrasive materials, and as a popular collector specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is traditionally called rock crystal or clear quartz.

Field identification & locations

Identify by its hardness (scratches glass), glass-like appearance, and lack of cleavage (breaks like glass into curved surfaces). Found globally in pegmatites and hydrothermal veins.