mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified July 7, 2026More mineral →

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Physical properties

Hardness: 7 on 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

Forms in hydrothermal veins or as a major constituent in igneous, metamorphic, and sedimentary rocks. Common in pegmatites. The milky color is caused by fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, and as a grit in sandpaper. In decorative forms, it is used for carvings, landscape stone, and occasionally in jewelry as cabochons.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is a common variety and is the state mineral of several regions. It often acts as a host rock for gold in hydrothermal veins.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and typical white, 'cloudy' appearance. It is found globally in riverbeds, mountains, and beaches.