mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: White to opaque white
Luster: Vitreous to greasy

Identified July 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins or as a primary constituent of many igneous and metamorphic rocks. The cloudy appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, as an abrasive, in electronic oscillators (if high purity), landscaping, and as a collector's specimen.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It can sometimes contain trace amounts of gold within its structure in specific geological mining districts.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white 'milky' appearance. It is found globally and is highly resistant to chemical and physical weathering.