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
Explore Milky Quartz in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

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 silica-rich hydrothermal fluids in veins or as a late-stage mineral in cooling igneous magmas. Found in almost all geological environments and ages.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), construction aggregates, and as a semi-precious gemstone in jewelry or decorative carvings.

Geological facts

The milky color is caused by tiny fluid inclusions of gas and/or liquid trapped during crystal growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white cloudy appearance. Common globally in mountain ranges and riverbeds.