mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically white or translucent, vitreous to greasy luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified July 30, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, typically white or translucent, vitreous to greasy luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

Forms in a wide variety of geological environments, most notably in igneous rocks such as granite and pegmatites, as well as hydrothermal veins and sedimentary deposits.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasive materials, gemstone carving, and mineral collections.

Geological facts

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

Field identification & locations

Easily identified by its hardness (scratches glass), lack of cleavage, and characteristic conchoidal fracture. Found worldwide in virtually every type of rock environment.