mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

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

Identified June 6, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed during the final stages of hydrothermal mineralisation in igneous veins or as masses in metamorphic rocks. The milky appearance is caused by tiny inclusions of liquid, gas, or both, trapped during crystal growth.

Uses & applications

Used as an abrasive in sandblasting, in the manufacture of glass and ceramics, as a flux in metallurgy, and as a decorative stone in landscaping or jewelry (cabochons).

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many prehistoric cultures to make stone tools where flint or chert was unavailable.

Field identification & locations

Identified by its white color, inability to be scratched by a steel knife, and lack of cleavage. It is found globally in almost every geological environment, often as large veins protruding from eroded landscapes.