mineral

Quartz (Smoky/Milky Variety)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Translucent tan to milky white. Luster: Vitreous (glassy). Crystal Structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Translucent tan to milky white
Luster: Vitreous (glassy)

Identified January 25, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Translucent tan to milky white. Luster: Vitreous (glassy). Crystal Structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. This specimen likely originated in a pegmatite or hydrothermal vein environment where mineral-rich hot water deposited silica in rock cavities.

Uses & applications

Used in glassmaking, abrasives, and as a gemstone. High-quality quartz is used in electronics for its piezoelectric properties. This rough specimen is primarily of interest for mineral collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'Quarz' and historically was believed by some ancient cultures to be 'permanent ice.'

Field identification & locations

Identify in the field by its hardness (it should scratch glass), lack of cleavage, and glassy appearance. Commonly found in mountainous regions, riverbeds, and as a primary component of granitic rocks.

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