mineral

Polished smoky quartz

Quartz (SiO₂), smoky variety

AI-generated identification · may be incorrect

Translucent to opaque smoky gray-brown with a vitreous polish; Mohs hardness 7, trigonal crystal structure, no cleavage and conchoidal fracture. The rounded form is tumbled or otherwise shaped.

Identified October 14, 2026More mineral →

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Physical properties

Translucent to opaque smoky gray-brown with a vitreous polish; Mohs hardness 7, trigonal crystal structure, no cleavage and conchoidal fracture. The rounded form is tumbled or otherwise shaped.

Formation & geological history

Smoky quartz forms in silica-rich veins and cavities as hydrothermal fluids cool; its color commonly results from natural irradiation acting on trace aluminum. Quartz occurs in rocks of many ages, so the specimen’s geological age cannot be determined from the image.

Uses & applications

Used for jewelry, carvings, ornaments, and mineral collecting.

Geological facts

Quartz is one of Earth’s most abundant minerals; smoky coloration ranges from pale gray to nearly black.

Field identification & locations

Identify by its glassy luster, hardness, lack of cleavage, and smoky tint; common sources include Brazil, Madagascar, and the Alps. The image shows a polished specimen, so locality and exact variety are uncertain.