mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions or within igneous pegmatites. It can be found in rocks of all geological ages.

Uses & applications

Used in electronics (oscillators), glassmaking, abrasives, jewelry (gemstones), 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 Greek word 'krustallos', meaning ice, as ancient Greeks believed it was ice frozen so hard it would never melt.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and hexagonal crystal habit. Found globally, especially in mountainous regions like the Alps, Himalayas, and Arkansas, USA.