mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 Mohs scale; Color: Milky white to pale yellow; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct; Specific Gravity: 2.65

Hardness: 7 Mohs scale
Color: Milky white to pale yellow
Luster: Vitreous to greasy

Identified May 28, 2026More mineral →

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Physical properties

Hardness: 7 Mohs scale; Color: Milky white to pale yellow; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct; Specific Gravity: 2.65

Formation & geological history

Forms through the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous rocks like granite. Often found in metamorphic environments.

Uses & applications

Used in glass making, electronics, jewelry (cabochons), and as an abrasive in construction and sandblasting. Also popular as decorative landscaping stone.

Geological facts

The milky appearance is caused by tiny inclusions of gas and liquid that were trapped during the crystal's growth. It is one of the most common minerals in the Earth's crust.

Field identification & locations

Identified by its hardness (scratches glass), waxy luster when tumbled, and lack of true cleavage. Commonly found in riverbeds, gravel pits, and mountain ranges worldwide.