Rock Identifier
Milky Quartz (Silicon Dioxide (SiO2)) — mineral
mineral

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 More 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 from the cooling of silica-rich hydrothermal fluids in veins or as a primary mineral in igneous rocks like granite. The milky appearance is caused by tiny fluid or gas inclusions trapped during crystal growth.

Uses & applications

Used in the glass and ceramic industries, as an abrasive, in electronics for its piezoelectric properties, and as a decorative stone in landscaping or jewelry.

Geological facts

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

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and white color. It is commonly found in mountain ranges, stream beds, and quartz veins worldwide.