mineral

Quartz (Milky or Cloudy Quartz)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale. Color: Translucent white to grey with cloudy appearance. Luster: Vitreous (glassy) to greasy. Crystal structure: Hexagonal/Trigonal. Cleavage: Indistinct/None (Conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Translucent white to grey with cloudy appearance
Luster: Vitreous (glassy) to greasy

Identified March 28, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust and can be found in geological formations ranging from billions of years old to modern precipitates.

Uses & applications

Used in glassmaking, abrasives, and as a component in concrete. In jewelry, it is used for beads and carvings. It is also used in electronics (oscillators) and 'healing' crystal collections.

Geological facts

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

Field identification & locations

Identify in the field by its hardness (will scratch glass and steel), lack of cleavage (breaks like glass), and waxy/vitreous luster. Common in granitic rocks and as mountain 'vein' material. It is a staple specimen for beginner collectors.

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