mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to opaque; 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 opaque
Luster: Vitreous to greasy

Identified June 19, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to opaque; 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 fluids in veins or as a major constituent of igneous rocks like granite. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), landscaping, and as a semi-precious gemstone in jewelry and carving.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically is common in gold-bearing quartz veins and was historically a 'guide mineral' for prospectors.

Field identification & locations

Identify in the field by its hardness (will scratch glass), white color, and lack of cleavage. Commonly found in riverbeds, mountain ranges, and gravel pits globally.