mineral

Clear Quartz

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 10, 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 a wide variety of environments, most commonly from the cooling of silica-rich magma or through hydrothermal activity in veins. It can be found in rocks from almost all geological ages.

Uses & applications

Used extensively in electronics for its piezoelectric properties, glassmaking, abrasives, jewelry (as 'Rock Crystal'), and widely collected as metaphysical or decorative specimens.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It was historically believed by the Greeks to be ice that had frozen so hard it would never melt, hence the name 'krustallos' (ice).

Field identification & locations

Identify in the field by its hardness (will scratch glass and steel), lack of cleavage, and hexagonal crystal points. It is found globally, with massive deposits in Brazil, the USA (Arkansas), and Madagascar.