mineral

Quartz (Smoky/Druzy variety)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Grayish-brown to translucent white; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Grayish-brown to translucent white
Luster: Vitreous to greasy

Identified June 23, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Grayish-brown to translucent white; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through hydrothermal processes in veins or pegmatites where silica-rich fluids cool and crystallize over geological time. Smoky coloration often results from natural irradiation of aluminum impurities.

Uses & applications

Commonly used in jewelry as gemstones, in watchmaking (oscillators), electronics (piezoelectric properties), and as decorative collector specimens.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Druzy refers to a coating of fine crystals on a rock surface, giving it a glittering appearance like sugar.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), its crystal habit, and its lack of cleavage. Often found in mountainous regions or inside geodes and rock cavities.