mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to translucent; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

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

Identified July 8, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to translucent; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins or as a late-stage crystallization in igneous rocks like granite. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used as a gemstone in jewelry, as an abrasive, in glass manufacturing, and in the semiconductor industry for its piezoelectric properties.

Geological facts

Milk quartz is the most common variety of crystalline quartz. It can often be found in large veins that are visible for miles in mountainous regions.

Field identification & locations

Identify by its hardness (it will scratch glass), its white 'cloudy' appearance, and its lack of cleavage. It is found globally in riverbeds, beaches, and mountain outcrops.