mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

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

Identified July 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments, most commonly from the cooling of silica-rich magma or from hydrothermal veins. It can form throughout all geological epochs.

Uses & applications

Used widely in electronics (piezoelectric properties), glass making, sandpaper (abrasives), jewelry, and as a popular collector's mineral.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust. The name 'quartz' comes from the German word 'Quarz', which likely originated from Slavic languages meaning 'hard'.

Field identification & locations

Identify by its glass-like appearance, inability to be scratched by steel, and conchoidal (shell-like) fracture patterns. Found globally, extremely common in mountains and riverbeds.