mineral

Milky Quartz in Siltstone or Feldspar

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Milky white to translucent with orange-brown matrix; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture)

Hardness: 7 on Mohs scale
Color: Milky white to translucent with orange-brown matrix
Luster: Vitreous (glassy)

Identified July 16, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent with orange-brown matrix; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture)

Formation & geological history

Formed from hydrothermal solutions or the cooling of silica-rich magma in veins. Often found in varying geological ages across igneous and metamorphic environments.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), and as decorative stones or gemstones in jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its cloudy appearance from microscopic inclusions of fluids or gas trapped during crystal growth.

Field identification & locations

Identified in the field by its hardness (it will scratch glass), its lack of cleavage, and its vitreous luster. Found worldwide in nearly all geological environments.