mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

Identified June 19, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from cooling magma or hydrothermal veins. It is found in a wide variety of geological environments including igneous, metamorphic, and sedimentary settings across all geological ages.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, construction aggregates, and occasionally as minor gemstone or decorative material.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its characteristic white color from microscopic inclusions of gas or liquid that were trapped during crystal growth.

Field identification & locations

Identify by its hardness (cannot be scratched by a steel knife), lack of cleavage, and glassy appearance. Extremely common worldwide, especially in riverbeds, mountains, and sandy soils.