mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified July 18, 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; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins, or as a primary mineral in igneous rocks like granite. The white color is caused by tiny fluid inclusions trapped during growth.

Uses & applications

Used in glass making, abrasive manufacturing, as a source of silicon for electronics, and commonly as decorative gravel or landscaping stone.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. Milky quartz is the most common variety of crystalline quartz found in nature.

Field identification & locations

Identify by its hardness (it will scratch glass), waxy/glassy appearance, and lack of cleavage. Often found as rounded pebbles in stream beds or as veins in mountain outcrops. Found globally.