mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Opaque white (milky)
Luster: Vitreous to greasy

Identified June 16, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. The milky appearance is caused by microscopic inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and abrasives. Also used as a gemstone in tumbled form, decorative landscaping, and as a source of silicon for electronics.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz can sometimes contain inclusions of gold or other valuable ores.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and characteristic white waxy luster. Common in many geological environments worldwide, especially in mountain ranges.