mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White to translucent cloudiness, Luster: Vitreous to greasy, Crystal structure: Hexagonal/Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified June 2, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White to translucent cloudiness, Luster: Vitreous to greasy, Crystal structure: Hexagonal/Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions or within cooling igneous magma. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used as a decorative gemstone, in the manufacturing of glass and ceramics, as an abrasive, and in the electronics industry due to piezoelectric properties when pure.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It is white and opaque because of the presence of numerous small 'veils' of fluid and gas bubbles. It is frequently found in hydrothermal veins and pegmatites.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and white cloudy appearance. It is found globally, particularly in areas with mountain-building activity or volcanic history. It is highly resistant to chemical and physical weathering.