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 July 10, 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

Forms in hydrothermal veins or as a primary constituent in igneous rocks like granite. The milky appearance is caused by tiny liquid or gas inclusions trapped during crystal growth.

Uses & applications

Used as a source for silicon, in glassmaking, as an abrasive, in electronics (piezoelectric properties), and as decorative landscaping stone or crystal healing specimens.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is specifically white because of 'fluid inclusions'—microscopic bubbles of water or gas trapped inside the crystal as it grew.

Field identification & locations

Identified in the field by its hardness (it scratches glass), lack of cleavage, and white opaque appearance. It common in mountainous regions with high metamorphic or igneous activity.