mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: White to translucent
Luster: Vitreous (glassy) to greasy

Identified June 28, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous rocks like granite. The milky appearance is caused by microscopic fluid inclusions trapped during crystal growth.

Uses & applications

Used as a gemstone (tumbled or cabochon), in glass manufacturing, as a source of silicon for electronics, and in decorative landscaping.

Geological facts

Quartz is one of the most abundant minerals in the Earth's continental crust. Milky quartz is the most common variety of crystalline quartz.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and characteristic milky-white translucency. It is found globally, particularly in mountainous regions and riverbeds.