mineral

Quartz (Smoky or Citrine variety)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: yellowish-brown to tan; Luster: Vitreous/glassy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: yellowish-brown to tan
Luster: Vitreous/glassy

Identified June 24, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: yellowish-brown to tan; Luster: Vitreous/glassy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through hydrothermal processes or in pegmatites. It crystallizes from molten silica-rich fluids as they cool in Earth's crust. Most specimens are millions of years old.

Uses & applications

Used in jewelry as gemstones, in manufacturing glass, and in electronics for its piezoelectric properties. Highly sought after by mineral collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'Quarz', which has Slavic origins meaning 'hard'.

Field identification & locations

Identify in the field by its hardness (will scratch glass) and lack of cleavage. Found globally in deserts, mountains, and riverbeds. Look for glassy luster and hexagonal crystal faces.

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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Metamorphic Rock

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mineral