mineral

Milky 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 22, 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 through the cooling of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. The white color is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and abrasives. Also used in construction as aggregate, in landscaping, and occasionally as a semi-precious gemstone or for ornamental carvings.

Geological facts

Milky Quartz is the most common variety of crystalline quartz found on Earth's crust. It often forms the 'vein' material seen in other rocks where gold or other metals may be deposited.

Field identification & locations

Identify in the field by its white color, ability to scratch glass (hardness 7), and lack of cleavage (it breaks in irregular, shell-like curves). It is found globally in almost all geological environments.