mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

Identified June 15, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins through the precipitation of silica from hot, mineral-rich solutions cooling down, or within igneous rocks like granite during crystallization of magma.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, jewelry (as semi-precious stones), and as a flux in metallurgical processes.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and characteristic waxy or vitreous luster. Commonly found worldwide in mountain ranges and riverbeds.