mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 Mohs scale; Color: Milky white with iron oxide staining (brownish-orange); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture).

Hardness: 7 Mohs scale
Color: Milky white with iron oxide staining (brownish-orange)
Luster: Vitreous to greasy

Identified July 18, 2026More mineral →

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Physical properties

Hardness: 7 Mohs scale; Color: Milky white with iron oxide staining (brownish-orange); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture).

Formation & geological history

Forms through the crystallization of silica-rich hydrothermal fluids in veins or geothermal environments. It is often found as hydrothermal vein filling in igneous and metamorphic rocks.

Uses & applications

Used as a source of silicon for semiconductors, glass making, abrasives, and as decorative stone in landscaping or lapidary arts.

Geological facts

The milky appearance is caused by tiny fluid inclusions of gas and/or liquid trapped during crystal growth. It is one of the most common minerals on the Earth's crust.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and white-to-stained appearance. Highly common in mountain streams and gold-bearing regions.