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 March 22, 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 primary constituent in igneous rocks. It can range in age from millions to billions of years old depending on the host rock formation.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive, in the electronics industry for its piezoelectric properties, and commonly as crushed stone in construction or landscaping.

Geological facts

Milky quartz gets its cloudy white appearance from tiny fluid inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz found on Earth.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and white 'milky' appearance. It is abundant worldwide in mountains, riverbeds, and as common pebbles. Collectors look for pieces with distinct crystal faces or gold inclusions.