Mineral

Milky Quartz

Silicon Dioxide (SiO₂)

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

Identified March 30, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of silica from hydrothermal solutions or cooling magma. Its white opacity is caused by microscopic inclusions of gas or liquid trapped during crystal growth. It can be found in veins or as river-worn pebbles across all geological ages.

Uses & applications

Used in the glass manufacturing industry, as an abrasive, in electronics (due to piezoelectric properties), construction gravel, and as ornamental landscaping stone or tumbled pocket stones.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. While it lacks the transparency of rock crystal, it can contain traces of gold in hydrothermal veins, making it an indicator mineral for prospectors.

Field identification & locations

Identify in the field by its ability to scratch glass, its waxy to vitreous luster, and lack of cleavage. Look for it in riverbeds or pegmatite outcrops. Often found globally, particularly in mountainous or volcanic regions.