mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to opaque; Luster: Glassy to greasy; Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to opaque
Luster: Glassy to greasy

Identified April 6, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to opaque; Luster: Glassy to greasy; Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from the crystallization of silica-rich magma or precipitation from hydrothermal veins. The white 'milky' color is caused by tiny inclusions of gas or liquid trapped during crystal growth. It can be found in rocks from almost any geological age.

Uses & applications

Used in electronics for its piezoelectric properties, as an abrasive in sandblasting, in glassmaking, and frequently as decorative landscaping stone or as jewelry in the form of tumbled stones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of crystalline quartz and is often found in massive form rather than distinct geometric crystals.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel), white color, and lack of cleavage. Often found near granite outcrops, in riverbeds, or as veins in mountain ranges.