mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from hydrothermal solutions or within pegmatites during the late stages of magmatic crystallization. It is common in veins across various geological ages and environments.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as decorative gravel or landscaping stone. Low-grade specimens are common in beginner rock collections.

Geological facts

The 'milky' appearance is caused by 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 in the field by its hardness (scratches glass), white color, and distinct waxy/greasy luster on broken surfaces. Often found as vein material in igneous or metamorphic terrain.