mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to opaque; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to opaque
Luster: Vitreous to greasy

Identified May 4, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to opaque; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms during the final stages of hydrothermal vein mineralization or within igneous pegmatites. The milky appearance is caused by tiny fluid or gas inclusions trapped during crystal growth.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), abrasives, and as a decorative stone in landscaping and jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is often found in massive form rather than distinct crystals.

Field identification & locations

Identified in the field by its hardness (it will scratch glass), its white color, and its lack of cleavage. It is found globally in many geological environments including mountains and riverbeds.