mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 Mohs
Color: White to translucent cloudy
Luster: Vitreous to greasy

Identified July 1, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms through the cooling of silica-rich magma or from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's formation. Found in a wide variety of geological ages and environments globally.

Uses & applications

Used in glass making, ceramics, and abrasives. In gemstone form, it is used for tumbled stones, decorative carvings, and metaphysical jewelry. It is also a source of silicon for electronics.

Geological facts

Milky Quartz is one of the most common minerals found on the Earth's crust. It often occurs as the 'matrix' or host rock for precious metals like gold in hydrothermal veins.

Field identification & locations

Identified by its ability to scratch glass (Hardness 7), its opaque white color, and the lack of cleavage planes. It is everywhere: found in mountains, riverbeds, and as pebbles on beaches. Collectors should look for large, well-formed hexagonal points in pegmatite zones.