mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, vitreous to greasy luster, clear to white or various shades of yellow/brown, conchoidal fracture, hexagonal crystal system, specific gravity of 2.65.

Identified August 3, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, vitreous to greasy luster, clear to white or various shades of yellow/brown, conchoidal fracture, hexagonal crystal system, specific gravity of 2.65.

Formation & geological history

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks, often crystallizing from hydrothermal veins or silica-rich magmas.

Uses & applications

Used in electronics, watches, glassmaking, abrasives, and as gemstones or ornamental specimens in jewelry.

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 under mechanical stress.

Field identification & locations

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