mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture.

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified July 9, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture.

Formation & geological history

Forms in hydrothermal veins or as a constituent in igneous, metamorphic, and sedimentary rocks. Often found in pegmatites or as a major part of common granite.

Uses & applications

Used in glassmaking, abrasives, construction as aggregate, and as a popular decorative or landscaping stone. It is also a source for silicon chips in electronics.

Geological facts

The white 'milky' color is caused by tiny liquid or gas inclusions trapped during the crystal's formation. It is the most common variety of crystalline quartz found on Earth's surface.

Field identification & locations

Identify in the field by its hardness (can scratch glass/steel), lack of cleavage, and white opaque appearance. Common in the central Mexican volcanic belt where hydrothermal activity is prevalent.