mineral

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque white; Luster: Vitreous to greasy; Crystal structure: Trigonal; Cleavage: Indistinct/None (Conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Cloudy white to opaque white
Luster: Vitreous to greasy

Identified April 10, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque white; Luster: Vitreous to greasy; Crystal structure: Trigonal; Cleavage: Indistinct/None (Conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and pegmatites through the cooling of silica-rich fluids. It can be found in a wide variety of geological environments and ages, often as a primary mineral in igneous and metamorphic rocks.

Uses & applications

Used as an abrasive in industrial applications, as a source for silicon in electronics, for decorative landscaping, and occasionally in inexpensive jewelry or carvings.

Geological facts

The white 'milky' appearance is caused by tiny inclusions of gas or liquid trapped within the crystal during growth. It is the most common variety of crystalline quartz found on Earth.

Field identification & locations

Identify in the field by its white color, lack of cleavage, and ability to scratch glass. It is commonly found in gravel beds, mountain streams, and as veins in larger rock outcroppings globally.