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 24, 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, pegmatites, and various igneous, metamorphic, and sedimentary rocks when silica-rich fluids cool and crystallize, trapping tiny gas or liquid bubbles that cause the milky white appearance.

Uses & applications

Used in manufacturing quartz glass, electronics (piezoelectric applications), abrasives, ceramics, and popular as an ornamental stone and mineral specimen for collectors.

Geological facts

The milky white color is caused by microscopic fluid inclusions (tiny pockets of gas or liquid) trapped inside the crystal structure during its formation millions of years ago.

Field identification & locations

Can be identified by its milky white translucence, glass-like luster, lack of cleavage, and ability to easily scratch glass (hardness 7). Commonly found worldwide in granitic environments and gravel deposits.