mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: White to cloudy translucent
Luster: Vitreous to greasy

Identified March 8, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to cloudy 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 magma or from hydrothermal veins. The white 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. Can be found in rocks of all geological ages.

Uses & applications

Used in the production of glass, ceramics, and sandpaper; as a source of silicon for electronics; in landscaping; and as a common specimen for rock collectors.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many indigenous cultures to create sharp stone tools and arrowheads through knapping.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), its white waxy appearance, and lack of cleavage planes. Frequently found in riverbeds, mountain veins, and as a component of granite. Look for the characteristic conchoidal (shell-like) fracture pattern.