mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to white/translucent; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

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

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless to white/translucent; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Formation & geological history

Forms in a wide variety of environments, including igneous crystallization (from magma), hydrothermal veins, and by precipitation from hot aqueous solutions. It is found in all geological ages.

Uses & applications

Used extensively in glassmaking, electronics (piezoelectric crystals), abrasives, construction (as sand/aggregate), and as a gemstone or ornamental stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is extremely resistant to chemical and physical weathering, which is why it often dominates beach sands.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and glassy appearance. It is found globally in almost every geological setting.