mineral

Smoky quartz (likely)

Quartz, silicon dioxide (SiO₂), smoky variety

AI-generated identification · may be incorrect

Translucent brown-gray, vitreous luster, typically hexagonal crystal structure, conchoidal fracture, Mohs hardness 7, and specific gravity about 2.65. The piece appears rough or partially cut, with surface damage and possible inclusions.

Identified September 22, 2026More mineral →

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Physical properties

Formation & geological history

Smoky quartz forms when natural radiation or trace aluminum colors quartz in granitic pegmatites, hydrothermal veins, and metamorphic rocks. Individual crystals may range from recent geologic growth to hundreds of millions of years old.

Uses & applications

Used as a collectible mineral and occasionally in ornamental objects and jewelry; gem-quality material is faceted or cabochon-cut. Common rough specimens have modest value.

Geological facts

Its smoky color is commonly caused by irradiation of aluminum-bearing quartz. Very dark material may be called morion, while pale material is often called cairngorm.

Field identification & locations

Identify it by hardness, glassy luster, lack of cleavage, and smoky transparent color; it should scratch ordinary glass but not be scratched by a steel knife. Common localities include Brazil, Madagascar, Switzerland, the United States, and Scotland.