mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to opaque; Luster: Vitreous to greasy; Crystal Structure: Trigonal (hexagonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

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

Identified July 20, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to opaque; Luster: Vitreous to greasy; Crystal Structure: Trigonal (hexagonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed primarily from hydrothermal solutions in veins or as a late-stage crystallization in igneous rocks like granite. Common in various geological environments from Precambrian to recent times.

Uses & applications

Used in construction as a raw material, silicon production for electronics, decorative landscaping, and as a component in glass manufacturing.

Geological facts

Milky quartz gets its cloudy appearance from microscopic inclusions of fluids (liquid or gas) trapped inside the crystal during its formation. It is the most common variety of crystalline quartz.

Field identification & locations

Identified in the field by its white color, hardness (it scratches glass effortlessly), and lack of cleavage. Found globally in all rock types, especially near quartz veins and in riverbeds.