mineral

Quartz (Smoky/Milky variety)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to pale brown/grey; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Cloudy white to pale brown/grey
Luster: Vitreous (glassy)

Identified July 6, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to pale brown/grey; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments through the cooling of silica-rich magma or precipitation from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust.

Uses & applications

Widely used in glassmaking, electronics (piezoelectric properties), abrasives, construction sand, and as a semi-precious gemstone in jewelry or for metaphysical collecting.

Geological facts

Quartz is highly resistant to chemical and physical weathering. Smoky quartz gets its darker color from natural radiation in the earth acting on aluminum impurities within the crystal lattice.

Field identification & locations

Identify in the field by its ability to scratch glass, lack of cleavage (it breaks like glass), and its hexagonal crystal habit. It is found globally, common in riverbeds and mountain ranges.