mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless, white, grey, purple, pink, brown, etc.; Luster: Vitreous (glassy); Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless, white, grey, purple, pink, brown, etc
Luster: Vitreous (glassy)

Identified July 31, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks, often precipitating from hydrothermal veins and silica-rich solutions.

Uses & applications

Used in electronics, glassware, precision instruments, countertops, abrasive materials, and as gemstones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust, after feldspar. It exhibits piezoelectric properties, meaning it can generate an electric charge in response to applied mechanical stress.

Field identification & locations

Identified in the field by its distinctive crystal form, high hardness (scratches glass), lack of cleavage, and vitreous luster. Found worldwide in nearly every geological setting.