mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

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

Identified July 13, 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: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from silica-rich hydrothermal solutions or the cooling of magma in igneous rocks like granite. Its white color is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in landscaping, as an abrasive, in glassmaking, and in electronics for its piezoelectric properties. Common in lapidary for carvings and tumbled stones.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked by collectors seeking clear crystals, its white opacity can be quite striking when polished.

Field identification & locations

Identify in the field by its hardness (will scratch glass), conchoidal fracture, and lack of cleavage. Found worldwide in quartz veins and as a primary constituent of granitic rocks.