mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: White to milky translucent
Luster: Vitreous to greasy

Identified June 1, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to milky 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 as a primary constituent of cooling igneous rocks like granite. It is one of the most common minerals in the Earth's crust across all geological ages.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), jewelry (cabochons), and as a landscape stone. High-purity quartz is essential for making silicon chips.

Geological facts

The milky white color is caused by tiny inclusions of gas or liquid trapped during crystal growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and white opaque appearance. It is found globally in veins, pegmatites, and as rounded river stones.