mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to off-white, translucent to opaque; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: ~2.65

Hardness: 7 on Mohs scale
Color: White to off-white, translucent to opaque
Luster: Vitreous to greasy

Identified July 25, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to off-white, translucent to opaque; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: ~2.65

Formation & geological history

Forms in hydrothermal veins, pegmatites, and igneous rocks through the crystallization of silica-rich fluids. Often worn smooth as river or beach pebbles.

Uses & applications

Used in glassmaking, ceramics, electronics (as a source of silicon), abrasives, decorative landscaping, and by amateur rock collectors.

Geological facts

Milky quartz gets its cloudy white appearance from tiny fluid inclusions (gas or liquid trapped during crystal growth). It is one of the most abundant minerals on Earth's continental crust.

Field identification & locations

Identified by its harness (scratches glass, cannot be scratched by steel), waxy or vitreous luster, lack of cleavage, and characteristic milky white color. Commonly found in riverbeds, gravel deposits, and mountainous areas worldwide.