mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified April 19, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of magma or from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. It can be found in a variety of geological ages and environments.

Uses & applications

Used as an abrasive in sandblasting, in the manufacturing of glass and ceramics, and as a source of silicon for electronics. In slab form, it is used for countertops. It is also a popular stone for landscaping and as a beginner's collecting specimen.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. Its white color is essentially 'pollution' by fluids trapped within the crystal structure millions of years ago. It often acts as a 'host rock' for gold in hydrothermal veins.

Field identification & locations

Identify in the field by its white color, inability to be scratched by a steel knife (hardness 7), and lack of cleavage. It is found globally, common in riverbeds and mountainous regions.