mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous (glassy) to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous (glassy) to greasy

Identified March 8, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The white 'milky' appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth. They are found in geological environments ranging from Precambrian to Cenozoic.

Uses & applications

Used in glassmaking, abrasives, and as a source of silicon for electronics. In jewelry, it is often used for beads or cabochons. Massive varieties are used in construction as landscaping stone or aggregate.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is specifically associated with gold veins in many historic mining districts, as the two often precipitate together in hydrothermal systems.

Field identification & locations

Identify in the field by its ability to scratch glass, lack of cleavage, and waxy-to-glassy appearance. It is found globally in pegmatites, veins, and as pebbles in riverbeds. Beginners should look for the characteristic uneven fracture and hardness.