mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified April 6, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions in veins or as a primary constituent of igneous rocks like granite. Its cloudy appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, foundry sand, and as a source of silicon for electronics. In jewelry, it is often cut as cabochons or used for decorative carvings and landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically is the most common variety of crystalline quartz. It can often be found associated with gold in hydrothermal vein deposits.

Field identification & locations

Identify in the field by its white color, ability to scratch glass (hardness 7), and lack of cleavage (it breaks in irregular, curved 'shell-like' shards). Commonly found in mountain ranges, riverbeds, and as veins in metamorphic and igneous outcrops.