mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 13, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to creamy white; 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 through the cooling of silica-rich solutions. It occurs across all geological ages, predominantly in igneous and metamorphic environments.

Uses & applications

Used in construction as an aggregate, in landscaping, as a source for silicon in electronics, and in lapidary work for tumbled stones or cabochons.

Geological facts

Milky quartz gets its cloudy appearance from tiny inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz found on Earth.

Field identification & locations

Identify by its hardness (scratches glass), white color, and lack of cleavage. It is ubiquitous in riverbeds, mountains, and rocky soils globally. Small tumbled pieces are common in beginner rock collections.