mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to white; Luster: Vitreous; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to white
Luster: Vitreous

Identified July 9, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless to white; Luster: Vitreous; 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 magma or hydrothermal veins. It is a major constituent of igneous, metamorphic, and sedimentary rocks across all geological ages.

Uses & applications

Used in jewelry, watchmaking (piezoelectric properties), glassmaking, electronics, and as a popular collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is traditionally called rock crystal. It was historically believed by some cultures to be permanently frozen ice.

Field identification & locations

Identified by its hexagonal crystal habit, hardness (will scratch glass), and lack of cleavage. Found globally, with significant deposits in Brazil, Arkansas (USA), and Madagascar.