mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 22, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and pegmatites through the cooling of silica-rich fluids. Milky quartz specifically gets its appearance from tiny fluid or gas inclusions trapped during crystal growth. They can be found in rocks from almost any geological age.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive, in construction as decorative stone, and by gemstone collectors for tumbling and carving.

Geological facts

Milky quartz is one of the most common varieties of crystalline quartz. Historically, it has been used for hundreds of years in different cultures for ornamental purposes and was once used to help start fires when struck against steel.

Field identification & locations

Identify by its characteristic milky appearance, lack of cleavage, and ability to scratch glass (hardness 7). It is commonly found in gravel beds, mountain ranges, and near volcanic regions globally.