mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified April 12, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the cooling of magma or hydrothermal veins. The milky appearance is caused by tiny gas or liquid inclusions trapped during crystal growth. They can be hundreds of millions of years old depending on the local geology.

Uses & applications

Used in glass making, abrasive blasting, electronics (due to piezoelectric properties), construction aggregate, and as a common decorative collector's piece.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz found in nature. Historic cultures used it for making tools and as a medicinal stone.

Field identification & locations

Identify by its ability to scratch glass, its white 'milk' color, and the lack of cleavage planes. Found globally in almost any geological environment, especially riverbeds and mountainous terrain.