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 May 1, 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 solutions in veins or during the cooling of igneous magmas. Milky quartz gets its cloudiness from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and abrasives. Used as a gemstone for beads and carvings, and as a landscaping stone. It is also an important source of silicon for electronic components.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked by collectors for rarer varieties like amethyst, large hydrothermal veins can contain enormous masses of this mineral.

Field identification & locations

Identify in the field by its hardness (will scratch glass), white 'cloudy' appearance, and lack of cleavage planes. Found globally in almost all geological environments, especially in hydrothermal veins and pegmatites.