mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically white or colorless, vitreous to greasy luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified July 29, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, typically white or colorless, vitreous to greasy luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks. It crystallizes from silica-rich hydrothermal solutions and magmas, and is extremely resistant to weathering.

Uses & applications

Used widely in glassmaking, electronics, oscillators, abrasives, gemstones, and construction materials.

Geological facts

Quartz is one of the most abundant and widespread minerals on Earth's continental crust. It exhibits piezoelectric properties, meaning it can generate an electric charge under mechanical stress.

Field identification & locations

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