mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified May 23, 2026More mineral →

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Physical properties

Hardness: 7 (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

Formed in hydrothermal veins and pegmatites where silica-rich fluids cool slowly. It is found in a wide variety of igneous, sedimentary, and metamorphic environments globally and can date back billions of years.

Uses & applications

Used in glass making, abrasive manufacturing, electronics (due to piezoelectricity), and as a landscape or construction stone. Common specimens are used in lapidary work and as starter pieces for rock collectors.

Geological facts

Milkiness is caused by tiny inclusions of gas or liquid trapped during crystal growth. It is one of the most common minerals on Earth's crust and is often found as the 'vein mineral' in gold-bearing regions.

Field identification & locations

Identify by its white color, inability to be scratched by a steel knife, and lack of cleavage (it breaks in irregular, jagged shapes). It is extremely common in mountainous terrain and riverbeds.