mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to off-white with minor iron staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to off-white with minor iron staining
Luster: Vitreous to greasy

Identified July 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermally active environments, igneous intrusions, and pegmatites, as well as metamorphic hydrothermal veins where fluids deposit silicon dioxide over long periods.

Uses & applications

Used widely in glassmaking, electronics (piezoelectric applications), abrasives, as an aggregate in construction, and as decorative gravel or landscaping stone.

Geological facts

Milky quartz gets its cloudy white appearance from millions of microscopic fluid inclusions trapped during the crystal growth, which refract light throughout the mineral.

Field identification & locations

Can be identified by its distinctive white, semi-opaque appearance, lack of cleavage, and ability to easily scratch glass (hardness 7). Commonly found in stream beds, gravel deposits, and mountainous vein outcrops worldwide.