mineral

Quartz Crystal

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale, Color: Clear to white or milky, Luster: Vitreous (glassy), Crystal Structure: Trigonal, Cleavage: None (exhibits conchoidal fracture), Specific Gravity: 2.65

Identified July 31, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale, Color: Clear to white or milky, Luster: Vitreous (glassy), Crystal Structure: Trigonal, Cleavage: None (exhibits conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins, pegmatites, and as a primary constituent of many igneous, metamorphic, and sedimentary rocks over a vast range of geological ages.

Uses & applications

Used in electronics (oscillators), manufacturing of glass and ceramics, ornamental carvings, gemstones, and metaphysical collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust, following feldspar. It exhibits piezoelectric properties, meaning it can generate an electrical charge under mechanical stress.

Field identification & locations

Easily identified by its distinct hexagonal crystal faces (when present), high hardness of 7 (scratches glass), and conchoidal fracture. Found worldwide in nearly every geological environment.