mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 Mohs
Color: White to translucent
Luster: Vitreous to greasy

Identified May 29, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins, pegmatites, and as a primary mineral in igneous rocks like granite. The milky opacity comes from microscopic inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, as an abrasive, in electronics for its piezoelectric properties, in jewelry (tumbled stones), and as decorative landscaping gravel.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically gets its appearance from fluid inclusions of water or CO2 that scatter light.

Field identification & locations

Identified by its hardness (scratches glass but not vice versa), white color, and Lack of cleavage. Commonly found in riverbeds, beaches, and mountain outcrops globally.