mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified April 30, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent of igneous rocks like granite. Can form across various geological ages from Precambrian to Cenozoic.

Uses & applications

Used in glassmaking, as an abrasive, in electronics (piezoelectric properties), as a gemstone in tumbled jewelry, and as a decorative stone in landscaping.

Geological facts

The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during the crystal's growth. It is one of the most abundant minerals in the Earth's continental crust.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and white 'milky' opacity. Extremely common globally in mountain ranges and stream beds.