mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White/Translucent milky; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White/Translucent milky
Luster: Vitreous to greasy

Identified March 18, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White/Translucent milky; 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 or within igneous pegmatites. The milky appearance is caused by tiny liquid or gas inclusions trapped during crystal growth over millions of years.

Uses & applications

Used in glassmaking, abrasives, and as a source of silicon for electronics. In the gemstone world, it is often polished into cabochons or used for decorative carvings and landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. 'Milky Quartz' gets its name from the microscopic fluid bubbles that scatter light, creating its foggy appearance.

Field identification & locations

Identifiable in the field by its ability to scratch glass and lack of cleavage planes. It is globally common, found in almost every geological environment, especially in mountain ranges and riverbeds.