mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

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

Identified April 9, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. It commonly crystallizes from magma or precipitates from hydrothermal veins. It is found in geological formations of all ages.

Uses & applications

Used in electronics (oscillators), optics, glassmaking, abrasives, jewelry, and as a popular metaphysical or collectible gemstone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the Greek word 'krystallos,' meaning ice, as ancient Greeks believed quartz was permanently frozen ice.

Field identification & locations

Identify by its hardness (scratches glass), glass-like luster, and absence of cleavage. Found globally, especially in mountainous regions like the Alps, Brazil, and Arkansas, USA.