mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified July 13, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous rocks like granite. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the glass and ceramics industry, as a source for silicon, in construction as aggregate, and in landscaping or decorative gravel. Occasionally used for tumbled stones or low-cost lapidary work.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is specifically white because of 'fluid inclusions'—microscopic bubbles of water or air trapped within the crystal structure.

Field identification & locations

Identified in the field by its hardness (will scratch glass), white color, and lack of cleavage. It is found globally, particularly in mountainous regions and riverbeds as pebbles and boulders.