mineral

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

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

Identified April 3, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or pegmatites from cooling silica-rich fluids. It is often found as a primary mineral in igneous rocks like granite or as a secondary deposit in veins. Age can range from millions to billions of years depending on the host rock.

Uses & applications

Used in construction as crushed stone, in industrial glass making, as an abrasive, and in jewelry/decorative carvings. It is also a source of silicon for electronic components and solar panels.

Geological facts

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

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and white 'milky' color. Look for it in quartz veins cutting through other rock types or as pebbles in stream beds.