mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to white/milky; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to white/milky
Luster: Vitreous (glassy)

Identified June 29, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless to white/milky; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is a primary constituent of granite and other igneous rocks, and can be found in all types of geological environments across various ages.

Uses & applications

Used in electronics (oscillators), glass making, abrasives, construction as a component of concrete, and as gemstones (Amethyst, Citrine) or decorative specimens.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it generates an electric charge in response to mechanical stress, which is why it is used in watches.

Field identification & locations

Identify in the field by its hardness (it scratches glass), glassy luster, and lack of cleavage (it breaks in irregular, curved shards). Found globally in mountain ranges, desktops, and riverbeds.