mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified March 25, 2026More mineral →

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Physical properties

Hardness: 7 on the 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 from the crystallization of silica-rich hydrothermal fluids in veins or from cooling magma in pegmatites. The 'milky' appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth. They can range from Precambrian to recent geological ages.

Uses & applications

Used in jewelry (cabochons and beads), as a decorative landscaping stone, in glass manufacturing, and as a source of silicon for electronics. It is very popular for crystal healing and mineral collecting.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. Historically, it has been used for stone tools since the Stone Age. Significant specimens are often found in association with gold in hydrothermal veins.

Field identification & locations

Identify by its ability to scratch glass (hardness 7), lack of cleavage, and white cloudy appearance. Common worldwide, especially in metamorphic and igneous terrains. For collectors, look for well-defined hexagonal crystal points rather than massive chunks.