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 May 15, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

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 through the cooling of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous rocks like granite. The milky appearance is caused by tiny liquid or gas bubble inclusions trapped during crystal growth. Quartz exists across all geological eras.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, and as a semi-precious gemstone in jewelry or home decor. Common in construction as an aggregate.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz found in nature. It can often contain trace amounts of gold in hydrothermal veins.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and white 'cloudy' appearance. It is found globally in mountains, riverbeds, and beaches. For collectors, look for large, well-defined points or specimens with metal inclusions.