mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Cloudy white to grayish
Luster: Vitreous to greasy

Identified July 1, 2026More mineral →

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Physical properties

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

Formation & geological history

Found in hydrothermal veins and pegmatites. It forms as silica-rich fluids cool and crystallize in crustal openings. Milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the glass and ceramic industries, as a source of silicon for electronics, in landscaping, and sometimes for metaphysical or decorative collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The white 'milky' color is due to millions of microscopic bubbles that were trapped as the crystal was forming.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and waxy-to-glassy luster. It is highly resistant to weathering and often found as white pebbles in stream beds.