mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified July 18, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in a wide variety of environments, most commonly from hydrothermal veins and pegmatites. The milky white color is caused by tiny inclusions of gas and liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (due to piezoelectric properties), and as decorative stone or landscaping material.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It can often be found associated with gold in hydrothermal vein deposits. Its opacity is due to microscopic 'fluid inclusions' of water or gas.

Field identification & locations

Identify by its hardness (will scratch glass), white color, and lack of cleavage. It is found globally in igneous, metamorphic, and sedimentary rocks. Common in mountain ranges and riverbeds.