mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified March 1, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich hydrothermal solutions in veins or during the late-stage crystallization of igneous pegmatites. The white color is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, as an abrasive, in the ceramics industry, and as a source of silicon for electronics. Lower quality specimens are used for landscaping and construction aggregate.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz can sometimes contain microscopic 'pockets' of gold or other minerals if it formed in specific hydrothermal environments.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white 'milky' appearance. It is found globally in almost every geological environment, particularly in mountain ranges and riverbeds.