mineral

Quartz (Smoky/Grey variety)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Grayish-white to smoky; Luster: Vitreous/Glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Grayish-white to smoky
Luster: Vitreous/Glassy

Identified April 3, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Grayish-white to smoky; Luster: Vitreous/Glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich magma or from hydrothermal veins. It can be found in igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & applications

Used widely in glassmaking, electronics (piezoelectric properties), abrasives, construction sand, and as a popular semi-precious gemstone in jewelry and mineral collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'Quarz', which has Slavic origins meaning 'hard'.

Field identification & locations

Identify in the field by its hardness (it scratches glass), lack of cleavage, and glassy luster. Specimens are commonly found in gravel pits, mountain ranges, and near pegmatite veins.