mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to creamy; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to creamy
Luster: Vitreous (glassy) to greasy

Identified March 24, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to creamy; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling and crystallization of silica-rich hydrothermal fluids or magma. Milky quartz gets its characteristic white color from microscopic inclusions of gas or liquid trapped during crystal growth. It is found in all geological ages from Precambrian to recent.

Uses & applications

Used in the glass and ceramics industry, as an abrasive, in construction as aggregate, and in landscaping. While common, high-purity specimens are used in electronics for their piezoelectric properties.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by ancient civilizations for stone tools and weapons due to its hardness and the sharp edges produced by its conchoidal fracture.

Field identification & locations

Identify in the field by its inability to be scratched by steel, lack of cleavage, and typical white 'cloudy' appearance. It is found globally in veins, pegmatites, and as rounded pebbles in riverbeds or beaches.