mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 (Mohs scale)
Color: White to translucent
Luster: Vitreous to greasy

Identified March 16, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The white color is caused by tiny inclusions of liquid, gas, or both, trapped during crystal growth. They are found across all geological ages.

Uses & applications

Used in industry as a source of silica for glass and ceramics, as an abrasive, in decorative landscaping, and occasionally as a base material for inexpensive jewelry or carvings.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many cultures for stone tool making because of its hardness and sharp edges when fractured.

Field identification & locations

Identify in the field by its distinct white color, lack of cleavage, and ability to scratch glass. It is commonly found as pebbles in riverbeds or as veins in igneous and metamorphic rocks globally.