mineral

Milky Quartz

Silicon Dioxide (SiO2)

Mohs hardness: 7. Color: White to translucent cloudy. Luster: Vitreous to greasy. Crystal structure: Hexagonal/Trigonal. Cleavage: Indistinct/Conchoidal fracture. Specific gravity: 2.65.

Hardness: 7
Color: White to translucent cloudy
Luster: Vitreous to greasy

Identified July 3, 2026More mineral →

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Physical properties

Mohs hardness: 7. Color: White to translucent cloudy. Luster: Vitreous to greasy. Crystal structure: Hexagonal/Trigonal. Cleavage: Indistinct/Conchoidal fracture. Specific gravity: 2.65.

Formation & geological history

Forms in hydrothermal veins or as a late-stage crystallization in igneous rocks like pegmatites. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used as an abrasive, in glass making, as a gemstone for beads/cabochons, in electronics (piezoelectric properties), and as decorative landscaping stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz. Some milky quartz contains traces of gold in hydrothermal vein deposits.

Field identification & locations

Identify by its white cloudy appearance, inability to be scratched by a steel knife, and conchoidal (shell-like) fracture patterns. Frequently found in mountain ranges and stream beds worldwide.