mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: cloudy white or translucent with reddish-brown staining, Luster: vitreous to greasy, Crystal structure: Trigonal (hexagonal prisms), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified March 3, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal solutions in veins. Examples can be found in a wide range of geological ages from the Precambrian to recent, often occurring in igneous rocks like granite or metamorphic rocks like quartzite.

Uses & applications

Used in the glass industry, as an abrasive in sandblasting, in ceramics, and occasionally for decorative landscaping or low-cost lapidary work. It is also a source of high-purity silica for electronics.

Geological facts

Milky quartz gets its characteristic white color from microscopic inclusions of fluids (liquid or gas) trapped inside the crystal as it grew. It is one of the most common and widely distributed minerals on Earth's crust.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white waxy appearance. Commonly found in riverbeds, mountains, and mining tailings globally. Collectors look for large, well-formed crystals or those with unique mineral inclusions.