mineral

Milky Quartz

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 Mohs; Color: Opaque white; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 Mohs
Color: Opaque white
Luster: Vitreous to waxy

Identified July 13, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Opaque white; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins, pegmatites, and as a primary constituent in igneous rocks. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, jewelry (tumbled stones), and as a source of silicon for electronic components and solar panels.

Geological facts

Milky quartz is one of the most common varieties of crystalline quartz on Earth. Its white color is due to millions of microscopic bubbles that were trapped as the crystal formed.

Field identification & locations

Identify by its ability to scratch glass, lack of cleavage, and typical milky-white opacity. It is ubiquitous globally, often found as pebbles in riverbeds or veins in mountain ranges.