mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: White to translucent milky
Luster: Vitreous to greasy

Identified June 13, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms from the cooling of silica-rich hydrothermal veins or within pegmatites. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, as an abrasive, in electronics (piezoelectric properties), and frequently as a decorative landscaping stone or beginner's collection specimen.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While it lacks the clarity of rock crystal, it can sometimes contain inclusions of gold in certain hydrothermal vein deposits.

Field identification & locations

Identify by its ability to scratch glass, lack of cleavage, and waxy/vitreous luster. Common worldwide in mountainous regions and riverbeds. Look for the characteristic white, 'cloudy' opacity.