mineral

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to cloudy translucent, with yellowish iron staining; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Luster: Vitreous to greasy

Identified March 22, 2026More mineral →

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Physical properties

Formation & geological history

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

Uses & applications

Used widely in glassmaking, abrasives, and as a source of silicon for electronics. In construction, it is used as road base and aggregate. It is also a popular specimen for beginner collectors and is sometimes used in landscaping or costume jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz found globally. Historically, it was used by many cultures to create tools and arrowheads when flint was unavailable.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage, and its waxy/vitreous luster. This specimen shows 'iron staining' (the yellow patches), which is common in surface-collected quartz. It is found in almost every mountainous or rocky environment worldwide and often occurs in 'veins' within other rock types.