mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White to translucent gray, Luster: Vitreous to greasy, Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified March 29, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White to translucent gray, Luster: Vitreous to greasy, Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins through the precipitation of silica-rich fluids or within igneous pegmatites. It is found in geological formations ranging from Precambrian to Cenozoic eras.

Uses & applications

Used as an abrasive in industry, as a source for silicon in semiconductors, in glass making, and as a landscaping stone or decorative rock. Low-grade specimens are used in gravel.

Geological facts

The milky white color is caused by millions of tiny microscopic inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz on Earth.

Field identification & locations

Identify by its hardness (it scratches glass), conchoidal fracture, and lack of cleavage. Often found in riverbeds, mountains, and eroded igneous outcrops globally. Tips: Look for its distinct waxy luster when wet.