mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale (scratches glass). Color: White to off-white opaque. Luster: Vitreous to greasy. Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale (scratches glass)
Color: White to off-white opaque
Luster: Vitreous to greasy

Identified March 23, 2026More mineral →

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Physical properties

Formation & geological history

Forms in hydrothermal veins or as a secondary mineral in igneous, metamorphic, and sedimentary rocks. Tiny fluid inclusions of gas or liquid trapped during crystal growth create the cloudy white appearance.

Uses & applications

Used as an abrasive, in glassmaking, as a source for silicon, and in landscaping. Polished stones are used in inexpensive jewelry and metaphysical practices.

Geological facts

Milky quartz is the most common variety of crystalline quartz. The 'milkiness' is caused by millions of microscopic bubbles of fluid that were trapped when the crystal was forming millions of years ago.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by a steel knife), white color, and lack of cleavage (it breaks in irregular, glass-like curves). Found globally in riverbeds, mountains, and as garden stones.