mineral

Quartz (Gray/Smoky Variety)

Silicon Dioxide (SiO2)

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

Identified June 19, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in igneous rocks like granite, metamorphic rocks, and hydrothermal veins through the crystallization of silica-rich fluids. The gray color can be caused by natural irradiation of aluminum impurities.

Uses & applications

Used in electronics for its piezoelectric properties, glass manufacturing, abrasives, and as semi-precious gemstones in jewelry or for metaphysical collecting.

Geological facts

Quartz is one of the most abundant minerals on Earth's crust. It is highly resistant to both chemical and physical weathering, which is why it is the primary component of most river and beach sands.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and glassy appearance. Commonly found in stream beds, gravel pits, and mountainous regions worldwide.