mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, color ranges from clear/white to various shades due to impurities, vitreous (glassy) luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified July 31, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of geological environments, commonly crystallizing from silica-rich hydrothermal veins and magma, as well as being a primary component of many igneous, metamorphic, and sedimentary rocks.

Uses & applications

Used widely in glassmaking, electronics, oscillators, abrasives, gemstones, and ornamental objects.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust, after 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 easily), lack of cleavage, and characteristic conchoidal fracture. It is found worldwide in virtually every type of geological environment.