mineral

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

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

Identified July 1, 2026More mineral →

Explore Milky Quartz in the encyclopedia →

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: Opaque 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 and crystallization of silica-rich magma or from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), various industrial fillers, and for lapidary work like cabochons or landscaping ornaments.

Geological facts

Quartz is the most abundant mineral in the Earth's continental crust. Milky quartz is often found in massive vein deposits and is frequently associated with gold deposits in 'mother lode' veins.

Field identification & locations

Identify in the field by its distinct hardness (will scratch glass), lack of cleavage, and white greasy luster. Found worldwide, especially in mountain ranges and riverbeds as rounded pebbles.