mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified April 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The white 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. They can be found in geological formations ranging from billions of years old to relatively recent ones.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, as decorative stones in landscaping, and occasionally in jewelry as cabochons.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While it is less popular than clear 'rock crystal' for high-end jewelry, it is technically the same mineral with added microscopic fluid inclusions.

Field identification & locations

Identify in the field by its ability to scratch glass (hardness 7) and its lack of cleavage planes. It often shows oily or greasy-looking surfaces when broken. It is extremely common in riverbeds and mountainous terrain worldwide.