mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified July 19, 2026More mineral →

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Physical properties

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

Formation & geological history

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

Uses & applications

Used in glass making, ceramics, as an abrasive, in decorative landscaping, and occasionally as a low-cost gemstone or for carving. In industry, it is a source of silicon for electronics.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It is often found in massive form rather than distinct crystals. It is the official state mineral of New Hampshire, USA.

Field identification & locations

Identified in the field by its distinct white color, lack of cleavage, and ability to scratch glass easily. It is found globally, especially in mountain ranges and riverbeds.