mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 Mohs; Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Specific Gravity: 2.65

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

Identified July 19, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Specific Gravity: 2.65

Formation & geological history

Forms through the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous rocks like granite. Its cloudy appearance is caused by tiny fluid inclusions trapped during growth.

Uses & applications

Jewelry beads, ornamental carvings, glass manufacturing, and as a source of high-purity silicon for electronics.

Geological facts

Milky quartz is the most common variety of crystalline quartz. The 'milkiness' comes from microscopic bubbles of gas and liquid that were trapped when the crystal formed millions of years ago.

Field identification & locations

Identified by its white, opaque-to-translucent appearance and the ability to scratch glass. It is found globally, especially in mountain ranges and gravel deposits.