mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: White to translucent
Luster: Vitreous to greasy

Identified April 3, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. It can be found in a wide variety of geological ages and environments, from ancient metamorphic shields to active tectonic regions.

Uses & applications

Used in the production of glass, ceramics, and abrasives. High-purity quartz is essential for silica wafers in the electronics industry. It is also common in landscaping, as a gemstone (tumbled or carved), and for spiritual/collecting purposes.

Geological facts

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

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white, cloudy appearance. It is often found as veins cutting through or protruding from darker country rock. Common worldwide in mountainous and metamorphic terrains.