mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: Colorless to white/gray (milky), Luster: Vitreous to greasy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified July 19, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Colorless to white/gray (milky), Luster: Vitreous to greasy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Quartz forms in a wide variety of environments, including cooling magma (igneous), hydrothermal veins, and through metamorphism. It is one of the most common minerals in the Earth's crust.

Uses & applications

Used in glassmaking, abrasives, jewelry (as gemstones), electronics (piezoelectric properties), and as a primary component in building materials like concrete.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to both chemical and physical weathering.

Field identification & locations

Identify by its hardness (it scratches glass easily but cannot be scratched by a steel knife) and its lack of cleavage. It is found globally in almost all geological environments.