mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, vitreous luster, colorless to white (though can be various colors with impurities), no cleavage, conchoidal fracture, specific gravity of 2.65, trigonal crystal system.

Identified July 30, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of geological environments, most commonly in igneous rocks like granite and pegmatites, as well as hydrothermal veins and sedimentary rocks like sandstone. Ages range from Precambrian to recent.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasive materials, gemstones, and ornamental objects.

Geological facts

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

Field identification & locations

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