mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: Colorless to white/gray, Luster: Vitreous (glassy), Crystal system: Trigonal/Hexagonal, Cleavage: Indistinct (conchoidal fracture), Specific Gravity: 2.65

Identified May 29, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Colorless to white/gray, Luster: Vitreous (glassy), Crystal system: Trigonal/Hexagonal, Cleavage: Indistinct (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed from cooling magma in igneous rocks or precipitated from hydrothermal veins; common in all geological environments. Age varies by locality (billions to millions of years old).

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), abrasives, construction sand, and as decorative gemstones or collector specimens.

Geological facts

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

Field identification & locations

Identified by its ability to scratch glass, lack of cleavage, and glassy appearance. Found globally in mountains, rivers, and beaches. Collectors look for well-defined hexagonal crystal points.