mineral

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear to light smoky brownish-grey; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Clear to light smoky brownish-grey
Luster: Vitreous (glassy)

Identified June 21, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear to light smoky brownish-grey; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed from cooling magma or hydrothermal veins. This specimen shows signs of water-worn erosion, likely collected from a stream or river bed where it weathered out of igneous or metamorphic host rock.

Uses & applications

Used in jewelry, electronics (oscillator crystals), glassmaking, and as a popular collector's mineral. High-purity quartz is essential for manufacturing semiconductors and solar panels.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The smoky color is caused by natural irradiation of aluminum impurities within the crystal lattice.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage (breaks like glass), and greasy-to-vitreous luster. Common worldwide in granite and pegmatite deposits.

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Mineral/Rock

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