mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, milky white to clear color with yellowish-brown iron staining, vitreous to greasy luster, trigonal crystal system, conchoidal fracture, specific gravity of 2.65.

Identified August 1, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, milky white to clear color with yellowish-brown iron staining, vitreous to greasy luster, trigonal crystal system, conchoidal fracture, specific gravity of 2.65.

Formation & geological history

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

Uses & applications

Used in electronics, glassware, precision instruments, abrasives, gemstones, and ornamental objects.

Geological facts

Quartz is one of the most abundant and widely distributed minerals found at Earth's surface. It exhibits piezoelectric properties, meaning it can generate an electrical charge in response to mechanical stress, making it crucial for watches and electronic oscillators.

Field identification & locations

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