mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified July 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins, pegmatites, and as a primary mineral in igneous rocks like granite. The milky opacity is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, silicon production, electronics (piezoelectric properties), and as landscaping stone or decorative specimens.

Geological facts

Milky quartz is one of the most common varieties of crystalline quartz found on Earth. Large veins of it often carry gold in quartz-reef mining areas.

Field identification & locations

Identify in the field by its hardness (will scratch glass), white color, and lack of cleavage. It is found globally in almost all geological environments, especially in mountain ranges and gravel deposits.