mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to semi-translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Cloudy white to semi-translucent
Luster: Vitreous to greasy

Identified March 9, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The white color is caused by microscopic fluid inclusions of gas and/or liquid trapped during crystal growth. They can range from Precambrian to recent in geological age.

Uses & applications

Used as a source of silica for glassmaking, as a decorative stone in landscaping (quartz pebbles), in the manufacture of ceramics, and occasionally as a gemstone or for metaphysical collecting.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. While it lacks the clarity of Rock Crystal, it is essentially the parent material for more famous varieties like Amethyst or Citrine, which contain additional impurities or have undergone radiation.

Field identification & locations

Identify in the field by its distinct white 'cloudy' appearance, ability to scratch glass, and lack of cleavage (it breaks in curved surfaces). Found globally in pegmatites and metamorphic rocks; very common in riverbeds as rounded pebbles.