mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to white/milky; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to white/milky
Luster: Vitreous (glassy)

Identified July 20, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless to white/milky; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust and can be found in igneous, metamorphic, and sedimentary environments.

Uses & applications

Used extensively in glass making, electronics (due to piezoelectric properties), abrasives, construction sand, and as a gemstone/collector specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it generates an electric charge when mechanical pressure is applied, which is why it is used in watches and clocks.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), glassy luster, and lack of cleavage (it breaks in curved, shell-like patterns called conchoidal fractures). Common in granite outcrops and creek beds.