mineral
Smoky Quartz
Silicon Dioxide (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, brown to black color, vitreous luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.
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Physical properties
Hardness of 7 on the Mohs scale, brown to black color, vitreous luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.
Formation & geological history
Forms in pegmatites, hydrothermal veins, and igneous or metamorphic rocks through natural irradiation of crystalline quartz over millions of years.
Uses & applications
Used in gemstone jewelry, decorative carvings, optical components, and as a popular collector specimen.
Geological facts
The dark coloration results from free silicon formed when natural radiation alters the crystal lattice. It is the national gemstone of Scotland.
Field identification & locations
Identified by its brown-to-grey translucency, high hardness scratching glass easily, and hexagonal crystal habits. Found globally, notably in Brazil, Madagascar, and the Swiss Alps.
