mineral

Quartz

Silicon Dioxide (SiO2)

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

Identified June 2, 2026More mineral →

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Physical properties

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

Formation & geological history

Quartz forms in a wide variety of environments, most commonly by crystallizing from molten magma (top-most layer of the crust) or precipitating from hydrothermal veins. It is found in igneous, metamorphic, and sedimentary rocks across all geological ages.

Uses & applications

Quartz is essential in the production of glass, ceramics, and electronics (due to its piezoelectric properties). It is also widely used in construction as sand and in jewelry/watchmaking as gemstones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'quarz', which originally meant 'hard'. It is highly resistant to chemical weathering.

Field identification & locations

Identify by its hardness (will scratch glass but cannot be scratched by a steel knife), glassy luster, and lack of cleavage. Look for it in quartz veins, river beds, or as crystals in geodetic formations.