mineral

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Pale brown to smoky gray; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Pale brown to smoky gray
Luster: Vitreous (glassy)

Identified April 1, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Pale brown to smoky gray; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed from cooling silica-rich magma or hydrothermal solutions in veins. The smoky coloring occurs due to natural irradiation of silicon dioxide containing trace amounts of aluminum over millions of years.

Uses & applications

Used in gemstone jewelry, piezoelectric technology for watches/clocks, glass making, and as a popular specimen for mineral collectors.

Geological facts

Quartz is one of the most abundant minerals in the 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 can scratch glass), lack of cleavage, and glassy fracture surfaces. It is commonly found in riverbeds, mountains, and pegmatites worldwide.

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