mineral
Quartz (Milky/Smoky Quartz)
Silicon Dioxide (SiO2)
Mohs hardness 7, translucent to opaque white-grey color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture, specific gravity 2.65
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Physical properties
Mohs hardness 7, translucent to opaque white-grey color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture, specific gravity 2.65
Formation & geological history
Formed through magmatic crystallization in pegmatites and hydrothermal vein systems, as well as metamorphic processes, abundant across various geological periods
Uses & applications
Used widely as gemstone material, decorative mineral specimens, abrasives, glassmaking, and in electronics due to piezoelectric properties
Geological facts
Quartz is the second most abundant mineral in the Earth's continental crust. Fluid inclusions trapped during its crystallization can reveal ancient thermal conditions.
Field identification & locations
Identified by its scratch resistance against steel (Mohs 7), lack of distinct cleavage, and characteristic glassy sheen. Commonly found in granite rocks, pegmatite veins, and stream deposits worldwide.
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