mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear to white with orange-brown iron staining; Luster: Vitreous; Crystal System: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear to white with orange-brown iron staining
Luster: Vitreous

Identified June 13, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear to white with orange-brown iron staining; Luster: Vitreous; Crystal System: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

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

Uses & applications

Used in glass making, electronics (due to piezoelectric properties), abrasives, construction as aggregate, and semi-precious jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to chemical and physical weathering, which is why it is the primary component of most beach sands.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and glassy appearance. Iron staining (orange/brown) is common in surface specimens. It is found globally in igneous, metamorphic, and sedimentary environments.