mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Cloudy white to pale grey
Luster: Vitreous to greasy

Identified March 22, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of magma or from hydrothermal veins. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth. Can be found in geological formations spanning from the Precambrian to the present.

Uses & applications

Used in the glass industry, as an abrasive, in the production of silicon, and as a decorative stone in landscaping. Lower-grade specimens like this are often used for road aggregate or filler.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically gets its 'milkiness' from microscopic bubbles of water or CO2 that were present when the crystal was forming millions of years ago.

Field identification & locations

Identify by its ability to scratch glass, its lack of cleavage, and its waxy or vitreous luster. It is ubiquitous globally, often found in mountain ranges, stream beds, and quartz veins. Collectors look for pieces with unique inclusions or structural habits.