mineral

Quartz (Gray/Smoky Varieties)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Gray to translucent white; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Gray to translucent white
Luster: Vitreous (glassy)

Identified June 6, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Gray to translucent white; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

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

Uses & applications

Extensively used in glass making, electronics (piezoelectric properties), abrasives, construction as an aggregate, and as a gemstone for jewelry and décor.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust. Its name comes from the German word 'Quarz', which likely originated from Slavic terms for 'hard'.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and conchoidal (shell-like) fracture patterns. Found globally in mountains and riverbeds.