mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, color ranges from colorless to white, gray, purple, pink, etc.; vitreous luster; trigonal crystal system; no cleavage; specific gravity of 2.65.

Identified August 2, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, color ranges from colorless to white, gray, purple, pink, etc.; vitreous luster; trigonal crystal system; no cleavage; specific gravity of 2.65.

Formation & geological history

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

Uses & applications

Used in electronics, watches, glassmaking, ceramics, abrasives, and as a gemstone or ornamental stone in jewelry.

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 applied mechanical stress.

Field identification & locations

Easily identifiable in the field by its high hardness (scratches glass), conchoidal fracture, and lack of cleavage. Found worldwide in almost every rock type.