mineral

Quartz (Milky or Cloudy variety)

Silicon Dioxide (SiO2)

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

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

Identified March 21, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is found in a wide variety of geological environments and can be from any geological age (Archean to recent periods).

Uses & applications

Used extensively in glassmaking, electronic oscillators (piezoelectric properties), abrasives, and as a component in construction concrete. Polished pieces are used in jewelry and decorative carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is chemically very stable and resistant to weathering, which is why it is the primary component of most beach sand.

Field identification & locations

Identify in the field by its hardness (will scratch glass and steel), lack of cleavage, and glassy appearance on fresh surfaces. Found globally in mountains, riverbeds, and as veins within other rock types.

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