mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White, opaque to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White, opaque to translucent
Luster: Vitreous to greasy

Identified June 16, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White, opaque to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Commonly forms in hydrothermal veins, pegmatites, and as a primary mineral in igneous rocks like granite. Its milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used as an abrasive, in glassmaking, as a gemstone (for carvings and bulk jewelry), and as a landscape stone. High-purity quartz is vital for the electronics and semiconductor industry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Ancient Greeks believed it was ice that had frozen so hard it would never melt. Milky quartz often occurs in veins that may also contain gold.

Field identification & locations

Identify in the field by its hardness (it scratches glass easily but cannot be scratched by a steel knife) and lack of cleavage. Found globally in almost all geological environments.