mineral

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

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

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

Identified April 12, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or precipitation from hydrothermal veins. It can be found in all types of geological environments and spans nearly all geological ages.

Uses & applications

Used in electronics (oscillators), glassmaking, abrasives, jewelry (as a gemstone), and as a popular specimen for mineral collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'quarz', which likely has Slavic origins meaning 'hard'.

Field identification & locations

Identify by its hardness (scratches glass), glass-like luster, and lack of cleavage. It is found globally in pegmatites, river beds, and mountainous regions like the Alps or Arkansas, USA.