mineral

Quartz

SiO2 (Silicon dioxide)

Hardness: 7 (Mohs scale), Color: White to translucent, Luster: Vitreous, Crystal structure: Hexagonal, Cleavage: None (conchoidal fracture), Specific gravity: 2.65

Identified July 18, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White to translucent, Luster: Vitreous, Crystal structure: Hexagonal, Cleavage: None (conchoidal fracture), Specific gravity: 2.65

Formation & geological history

Forms in all types of rocks (igneous, sedimentary, metamorphic) usually crystallizing from magma or precipitating from hydrothermal veins. It is one of the most abundant minerals in the Earth's continental crust.

Uses & applications

Used in glassmaking, electronics (oscillators), abrasives, foundry sand, and as a semi-precious stone in jewelry or for decorative purposes.

Geological facts

Quartz is piezoelectric, meaning it generates an electrical charge when mechanical stress is applied. This property makes it essential in clocks, watches, and radios.

Field identification & locations

Can be identified by its hardness (scratches glass), lack of cleavage, and conchoidal fracture. Has a glassy luster and is often found in massive form as seen in the image. Frequently found worldwide.