mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Milky white to light grey
Luster: Vitreous to greasy

Identified July 17, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or pegmatites from silica-rich fluids. The milky appearance is caused by tiny inclusions of gas and/or liquid trapped during crystal growth. Can be found in various geological ages ranging from billions of years old to relatively young deposits.

Uses & applications

Used in glass making, ceramics, as an abrasive, and in the electronics industry for its piezoelectric properties. It is also used in landscaping, architecture, and as a collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky Quartz specifically gets its opacity from microscopic fluid inclusions of water or CO2 that scatter light. Huge veins of quartz can contain macroscopic amounts of gold in certain geological environments.

Field identification & locations

Identify by its hardness (will easily scratch glass) and lack of cleavage (breaks like glass into curved surfaces). It is ubiquitous globally and often found in riverbeds, mountains, and as boulders in glacial till.