mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

Identified April 10, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; 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 through the cooling of silica-rich magma or from hydrothermal solutions in veins. It is found in a wide variety of geological environments ranging from igneous intrusions to sedimentary deposits.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), construction as an aggregate, and as decorative gravel or low-cost gemstone in jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its white color from tiny fluid inclusions of gas and/or liquid trapped during crystal growth.

Field identification & locations

Identify by its hardness (it will scratch glass and steel), lack of cleavage, and white opaque appearance. Can be found worldwide in gravel pits, mountain streams, and rocky terrains.