mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to semi-translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Cloudy white to semi-translucent
Luster: Vitreous to greasy

Identified July 11, 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: Cloudy white to semi-translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Forms in a wide variety of environments, most commonly in hydrothermal veins and pegmatites. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. It is found in rocks of all geological ages.

Uses & applications

Used in glassmaking, as an abrasive, in the production of silicon, as a gemstone (tumbled or cabochons), and in landscaping or construction aggregate.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of crystalline quartz. It can sometimes contain inclusions of gold in hydrothermal veins.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white cloudy appearance. It is found globally in mountainous regions, riverbeds, and as a primary component of many sands.