mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to tan with iron staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture).

Hardness: 7 on Mohs scale
Color: Milky white to tan with iron staining
Luster: Vitreous to greasy

Identified July 20, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to tan with iron staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture).

Formation & geological history

Forms through the cooling of silica-rich magma or through hydrothermal veins in various geological environments across all ages of Earth's history.

Uses & applications

Used extensively in glassmaking, electronics (piezoelectric properties), abrasives, and construction as a component of sand and gravel.

Geological facts

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

Field identification & locations

Identify by its ability to scratch glass and its lack of cleavage. It is found globally in riverbeds, mountains, and desert sands. Look for its characteristic waxy or glassy luster on fresh surfaces.