mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Cloudy white to grayish
Luster: Vitreous to greasy

Identified April 4, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silica-rich hydrothermal fluids cooling in veins and cavities within igneous, metamorphic, or sedimentary host rocks. Its white color is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used as a gemstone (tumbled or cabochon), in glass making, as an abrasive, in the electronics industry for its piezoelectric properties, and as a decorative stone in landscaping.

Geological facts

Quartz is one of the most abundant minerals in the Earth's crust. Milky quartz is characterized by its opacity, which distinguishes it from rock crystal (clear quartz).

Field identification & locations

Identify in the field by its hardness (will scratch glass and steel), lack of cleavage, and conchoidal fracture. Found globally in almost any geological environment, particularly in mountain ranges and stream beds.