mineral

Quartz (Milky/Smoky variety)

Silicon Dioxide (SiO2)

Hardness: 7 Mohs; Color: Translucent white to light gray; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 Mohs
Color: Translucent white to light gray
Luster: Vitreous (glassy)

Identified April 7, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Translucent white to light gray; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed primarily from hydrothermal veins and cooling igneous pegmatites. It is the most abundant mineral in the Earth's crust, found in virtually all geological environments and ages.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), jewelry (semi-precious gemstone), and as a common component in construction materials like concrete and mortar.

Geological facts

Quartz crystals have piezoelectric properties, meaning they generate an electric charge when mechanical stress is applied. This makes them essential for clocks, watches, and radio transmitters.

Field identification & locations

Identified in the field by its hardness (it can scratch glass), lack of cleavage, and glassy appearance. Common in river beds, mountains, and beaches worldwide.