mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, clear to white color, vitreous luster, hexagonal crystal system, conchoidal fracture, and specific gravity of 2.65.

Identified July 29, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, clear to white color, vitreous luster, hexagonal crystal system, conchoidal fracture, and specific gravity of 2.65.

Formation & geological history

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

Uses & applications

Used in electronics, oscillators, glassmaking, abrasives, and as a gemstone or specimen in jewelry and crystal collecting.

Geological facts

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

Field identification & locations

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