mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous and metamorphic rocks. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and electronics; also used as an abrasive, in construction as aggregate, and as a semi-precious gemstone in jewelry and carving.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. Milky quartz specifically gets its color from microscopic bubbles of water or CO2 that scatter light passing through the crystal.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and white opaque color. Found globally in mountains, riverbeds, and as common beach pebbles.