mineral

Milky 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 6, 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 silica-rich magma or from hydrothermal veins where hot aqueous solutions deposit quartz in rock fractures. Its white color is caused by tiny fluid inclusions of gas and/or liquid trapped during crystal growth.

Uses & applications

Used widely in glass making, electronics (piezoelectric properties), abrasives, and as a semi-precious gemstone in jewelry or decorative carvings.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. Milky quartz is the most common variety of crystalline quartz found in nature.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), its white, cloudy appearance, and lack of cleavage. Often found in riverbeds as rounded pebbles due to its durability.