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 May 13, 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

Formation occurs in igneous, metamorphic, and sedimentary environments through the cooling of silica-rich magma or precipitation from hydrothermal veins. It can be found in rocks from all geological ages.

Uses & applications

Extensively used in electronics for its piezoelectric properties, glass manufacturing, timekeeping (watches), gemstone jewelry, and metaphysical collecting.

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 ancients believed it was permanently frozen ice.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and smooth, curved conchoidal fractures. Common worldwide, particularly in Brazil, Madagascar, and Arkansas, USA.