mineral

Cloud Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

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

Identified February 10, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to translucent; 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-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. The white 'cloudy' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used widely in glass making, abrasive manufacturing, electronics (due to piezoelectric properties), and as an ornamental stone in landscaping or low-cost jewelry.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked for clearer varieties like rock crystal, massive occurrences of milky quartz can contain significant veins of gold in certain geological settings.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and characteristic 'milky' white opacity. It is found globally, common in mountain ranges and riverbeds. Look for quartz veins in metamorphic or igneous host rocks.

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