mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified March 29, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich hydrothermal veins or within igneous pegmatites. The white color is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth. They are found in geological environments ranging from Precambrian to Cenozoic eras.

Uses & applications

Used as a primary source of silicon for semiconductors and glass manufacturing. Also used as decorative landscaping stone, in construction aggregates, and occasionally as a semi-precious gemstone for beads and carvings.

Geological facts

Milky Quartz is the most common variety of crystalline quartz on Earth. While it lacks the clarity of Rock Crystal, it is remarkably durable and resistant to chemical weathering, which is why it often remains as rounded cobbles in riverbeds long after other minerals have eroded.

Field identification & locations

Identify in the field by its ability to scratch glass, its milky-white appearance, and lack of cleavage planes. It is ubiquitous globally, especially in mountain ranges and gravel deposits. For collectors, look for specimens with large visible crystal faces.