Milky Quartz

Physical Properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; 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 hydrothermal solutions or the cooling of silica-saturated magma. The white 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & Applications

Used in the glassmaking and ceramic industries, as an abrasive, in the production of silicon metal, and in landscaping or as a collector's specimen.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is often found in gold-bearing hydrothermal veins and was historically used by prospectors to locate gold deposits.

Field Identification & Locations

Identify in the field by its white color, its inability to be scratched by a steel knife (hardness), and the absence of cleavage. It is found globally in igneous, metamorphic, and sedimentary environments.

Identified on: 4/13/2026

Mode: Standard