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 25, 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 hydrothermal processes, crystallization from cooling magma (igneous), or metamorphic dehydration. It can occur in veins across all geological ages, from Precambrian to the present.

Uses & applications

Used as an abrasive in industry, as a flux in metallurgy, in glassmaking, and in landscape construction. While low-value, it is also a popular beginner collecting specimen and is sometimes used for lapidary work.

Geological facts

Milky quartz gets its cloudy appearance from microscopic inclusions of fluids or gas trapped during the crystal's growth. It is the most common variety of crystalline quartz found on the Earth's surface.

Field identification & locations

Identify in the field by its hardness (will scratch glass and steel), white 'milky' color, and lack of cleavage. Often found in hydrothermal veins, mountain regions, and as cobbles in riverbeds. Look for crystalline structure in cavities.