mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified March 4, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through hydrothermal processes, pegmatites, and magmatic crystallization. It is found in igneous, metamorphic, and sedimentary rocks across all geological ages, often as veins filling rock fractures.

Uses & applications

Used in glassmaking, construction aggregates, electronics (piezoelectric properties), jewelry (cabochons), and as a landscape stone or minor collector specimen.

Geological facts

Milky quartz gets its white color from tiny microscopic inclusions of gas or liquid trapped during the crystal's formation. It is the most common variety of crystalline quartz on Earth.

Field identification & locations

Identify by its ability to scratch glass (hardness 7), lack of cleavage, and white 'milky' appearance. It is found globally in river beds, beaches, and mountain outcrops. Collectors look for pieces with inclusions or associated minerals like gold or pyrite.