mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to milky white with light yellowish iron staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to milky white with light yellowish iron staining
Luster: Vitreous to greasy

Identified July 22, 2026More mineral →

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Physical properties

Formation & geological history

Formed in a wide range of geological environments, primarily cooling from silica-rich magmas in intrusive igneous rocks, precipitating from hydrothermal fluids in veins, or recrystallizing during metamorphism.

Uses & applications

Extensively used in electronics (piezoelectric oscillators), glass manufacturing, abrasives, construction aggregates, lapidary arts, and gemstone jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It exhibits piezoelectricity, meaning it generates an electric charge under mechanical stress, which powers quartz watches.

Field identification & locations

Identified in the field by its scratch resistance (scratches glass readily), lack of cleavage, glassy/waxy luster, and conchoidal fracture. Commonly found in quartz veins, granite outcrops, gravel beds, and stream beds worldwide.