mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear, white, gray, brown, yellow, pink, red, or orange; Luster: Vitreous (glassy); Crystal structure: Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear, white, gray, brown, yellow, pink, red, or orange
Luster: Vitreous (glassy)

Identified July 28, 2026More mineral →

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Physical properties

Formation & geological history

Forms in virtually all geological environments—igneous, metamorphic, and sedimentary rocks—often crystallizing from silica-rich hydrothermal veins and pegmatites.

Uses & applications

Used in glassmaking, electronics (oscillator crystals), abrasive materials, gemstones, and ornamental objects.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust, surpassed only by feldspar. Its piezoelectric properties make it essential in watches and electronic devices.

Field identification & locations

Easily identified by its distinct hardness (scratches glass easily), lack of cleavage, and conchoidal fracture. Found worldwide in nearly every type of terrain.