mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, vitreous luster, conchoidal fracture, colorless to various shades of white, pink, or purple, trigonal crystal system, specific gravity of 2.65.

Identified July 31, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, vitreous luster, conchoidal fracture, colorless to various shades of white, pink, or purple, trigonal crystal system, specific gravity of 2.65.

Formation & geological history

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

Uses & applications

Used in electronics, oscillators, glassmaking, abrasives, gemstones, and ornamental items.

Geological facts

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

Field identification & locations

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