mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, vitreous to greasy luster, transparent to opaque, conchoidal fracture, specific gravity of 2.65, trigonal crystal system.

Identified July 30, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, vitreous to greasy luster, transparent to opaque, conchoidal fracture, specific gravity of 2.65, trigonal crystal system.

Formation & geological history

Formed in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks, often crystallizing from silica-rich hydrothermal solutions or cooling magma.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasives, and as gemstones or decorative specimens in jewelry and collecting.

Geological facts

Quartz is one of the most abundant and widely distributed minerals on Earth's continental crust and exhibits piezoelectric properties.

Field identification & locations

Identified by its high hardness (scratches glass), lack of cleavage, and conchoidal fracture. Found worldwide in nearly every type of rock environment.