mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified June 15, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White to translucent milky appearance, 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 magma or from hydrothermal veins. The milky color is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, abrasives, semiconductor industry as a source of silicon, and as decorative gravel or low-cost semi-precious stones in jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically is white because of tiny fluid bubbles trapped inside that scatter light.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and characteristic milky-white translucent color. Commonly found in riverbeds, mountain ranges, and near volcanic sites.