mineral

Milky quartz (rough quartz fragment)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Typically white to translucent with a glassy-to-waxy luster; Mohs hardness 7, no cleavage, conchoidal fracture, and trigonal crystal structure. The irregular, cloudy appearance is consistent with milky quartz, though the photograph alone cannot exclude pale calcite or glass.

Identified September 2, 2026More mineral →

Explore Milky quartz (rough quartz fragment) in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Forms in hydrothermal veins, pegmatites, and silica-rich igneous rocks when quartz crystallizes from hot fluids or cooling magma. Quartz is common from Precambrian to modern geological settings.

Uses & applications

Used for glass, ceramics, abrasives, engineered stone, and electronics; attractive pieces are sold as inexpensive mineral specimens. It is generally not gem quality.

Geological facts

The cloudy color results from microscopic fluid inclusions, fractures, or mineral impurities. Quartz can scratch ordinary steel and glass, helping distinguish it from calcite and man-made glass.

Field identification & locations

Common worldwide, including Brazil, Madagascar, the United States, and alpine regions; identify by hardness, lack of cleavage, and conchoidal fracture. A hardness or acid test should be done only on an inconspicuous area.