mineral

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

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

Identified June 27, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed via hydrothermal activity where mineral-rich water cools in rock fractures, or crystallizes from magma. Often found in pegmatites and hydrothermal veins. This specimen appears water-worn, likely from a fluvial or lacustrine environment.

Uses & applications

Used as a gemstone (cabochons), in abrasive manufacturing, as a source for silicon in electronics, and in glass making. Often collected as decorative garden stones or metaphysical specimens.

Geological facts

The 'milky' appearance is caused by tiny liquid or gas bubble inclusions trapped during the crystal's growth. It is the most common variety of crystalline quartz found on Earth.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white opaque color. Commonly found in riverbeds, mountains, and gravel pits across North America and Europe.