mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to opaque; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to opaque
Luster: Vitreous to greasy

Identified May 27, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to opaque; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms through the crystallization of silica-rich hydrothermal solutions in veins or as a late-stage mineral in igneous pegmatites. The milky appearance is caused by tiny liquid or gas inclusions trapped during crystal growth.

Uses & applications

Used in the glass making industry, as an abrasive, in electronics for its piezoelectric properties, as a decorative gemstone, and widely used in landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of crystalline quartz.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, grease-like luster on fractured surfaces, and characteristic white color. It is found globally in almost all geological environments.