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 26, 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 magma or from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas and liquid trapped during crystal growth. They are found across all geological ages, often in metamorphic and igneous environments.

Uses & applications

Used industrially in glass manufacturing, as an abrasive, and in electronics for its piezoelectric properties. In construction, it is used as road base or aggregate. It is also used in decorative landscaping and as jewelry (cabochons) or for metaphysical collecting.

Geological facts

Quartz is the most abundant mineral in Earth's continental crust. Milky quartz specifically gets its color from microscopic 'bubbles' of water or CO2. Historically, it was often used by ancient cultures to create stone tools when flint was unavailable.

Field identification & locations

Identify in the field by its hardness (it should easily scratch glass) and lack of cleavage. Look for it in river beds, mountain trails, or near granite outcrops. Its white, sugary to waxy appearance is a key marker.