mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified March 18, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent of igneous and metamorphic rocks. Most specimens date from the Precambrian to recent eras depending on the host rock.

Uses & applications

Used as an abrasive, in glassmaking, as a gemstone (semi-precious), and in the production of silicon wafers for electronics. It is also a very common collector's mineral.

Geological facts

Milky quartz gets its characteristic white color from microscopic fluid inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz found on Earth.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage (it breaks in irregular, curved shards), and its typical waxy or glassy luster. It is found globally in mountain ranges and creek beds.