mineral

Quartz

Silicon Dioxide (SiO2)

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

Identified August 4, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in virtually all environments—igneous, metamorphic, and sedimentary—often precipitating from hydrothermal veins or cooling from silica-rich magma.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasives, gemstones, and ornamental items.

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 electric charge under mechanical stress.

Field identification & locations

Identified by its high hardness (scratches glass), lack of cleavage, and distinct conchoidal fracture. Found worldwide in almost every geological setting.