mineral

Milky Quartz

Quartz / Silicon Dioxide (SiO2)

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

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

Identified April 15, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich magma or via hydrothermal activity in veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. Can be found in geological formations ranging from billions of years old to relatively recent.

Uses & applications

Used in the production of glass, ceramics, and abrasives. Also used as a flux in metallurgy, in electronic oscillators (due to piezoelectric properties when pure), and as decorative stone in landscaping or jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically gets its color from microscopic 'bubbles' of fluid trapped during the mineral's formation, which scatter light.

Field identification & locations

Identify in the field by its ability to scratch glass (Hardness 7), lack of cleavage, and white opaque color. It is often found as pebbles in river beds or as veins in igneous and metamorphic rocks.