mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on the Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous (glassy) to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on the Mohs scale
Color: Cloudy white to opaque
Luster: Vitreous (glassy) to greasy

Identified March 30, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous (glassy) 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 veins or from cooling magma in igneous rocks like granite. The 'milky' appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the manufacturing of glass, ceramics, and abrasives. In electronics, it is used for its piezoelectric properties. It is also common in jewelry as cabochons and used as decorative landscaping stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz and 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 planes. It is found globally in almost all geological environments, particularly in mountain ranges and stream beds.