mineral

Milky Quartz

Silicon dioxide (SiO2)

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

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

Identified July 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and pegmatites through the cooling of silica-rich solutions, often occurring as the last mineral to crystallize in magma. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in decorative landscaping, glass manufacturing, abrasives, electronics (piezoelectric properties), and frequently as pocket stones or in jewelry as cabochons.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. While it lacks the clarity of Rock Crystal, it is found in massive quantities across all continents and tectonic settings.

Field identification & locations

Identify in the field by its white color, inability to be scratched by a steel knife, and lack of cleavage. It is found globally in mountainous terrains and riverbeds. For collectors, look for pieces with interesting mineral inclusions or crystal faces.