mineral

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

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

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

Identified April 11, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in wide range of geological environments, most commonly from hydrothermal veins or as a primary constituent of granitic pegmatites. The milky white color is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, jewelry (as cabochons), and high-quality specimens are collected. Also holds historical industrial use in clocks and electronics due to piezoelectric properties.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was sometimes used by ancient civilizations for stone tools because of its hardness and the way it fractures into sharp edges.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife, its lack of cleavage, and its waxy or vitreous luster. It is ubiquitous in mountainous terrains and gravel deposits worldwide.