mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White to translucent Milky, Luster: Vitreous/Greasy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None (Conchoidal fracture), Specific Gravity: 2.65

Identified June 28, 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 (Mohs scale), Color: White to translucent Milky, Luster: Vitreous/Greasy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None (Conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous rocks like granite. The white color is caused by tiny inclusions of gas or liquid.

Uses & applications

Used in glassmaking, as an abrasive, in electronics (though clear quartz is preferred), as a gemstone in tumbled form, and in landscaping/construction.

Geological facts

Milky quartz is one of the most common minerals on Earth. Its cloudy appearance is due to 'fluid inclusions'—microscopic bubbles of water or gas trapped during the crystal's formation millions of years ago.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and characteristic milky white appearance. It is found globally, particularly in mountainous regions and riverbeds.