mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified July 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and pegmatites. The milky appearance is caused by tiny fluid or gas bubbles trapped during crystal growth. Found in many geological environments worldwide.

Uses & applications

Used in glass making, ceramics, as an abrasive, in the electronics industry for its piezoelectric properties, and as decorative stone or landscaping material.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically owes its color to the microscopic 'bubbles' of fluid that remained in the crystal as it grew.

Field identification & locations

Identified in the field by its hardness (it scratches glass), lack of cleavage, and white opaque color. Very common in mountainous regions and riverbeds.