mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale, Color: Colorless to white, gray, yellow, brown, or pink, Luster: Vitreous (glassy), Crystal System: Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified July 30, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale, Color: Colorless to white, gray, yellow, brown, or pink, Luster: Vitreous (glassy), Crystal System: Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of geological environments, most commonly in igneous rocks like granite and pegmatites, hydrothermal veins, and as detrital grains in sedimentary rocks.

Uses & applications

Used in electronics (quartz crystal oscillators), glassmaking, abrasives, gemstones, and ornamental objects.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust. It exhibits piezoelectric properties, meaning it generates an electric charge in response to mechanical stress.

Field identification & locations

Identified by its high hardness (scratches glass), vitreous luster, lack of cleavage, and conchoidal fracture. Found worldwide in nearly every type of geological environment.