mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to translucent
Luster: Vitreous to greasy

Identified July 13, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins and pegmatites when silica-rich fluids cool and crystallize. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. It can be found in rocks from all geological ages.

Uses & applications

Used as an abrasive, in glass making, ceramics, and as a semi-precious gemstone in jewelry (cabochons or beads). It is also a source of silica for industrial silicon production.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically is known for its high concentrations of fluid inclusions, which can contain information about the temperature and pressure during formation.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and white waxy appearance. Often found as veins running through darker rocks or as eroded pebbles in river beds. It is extremely common worldwide.