mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Mohs hardness: 7. Color: Opaque white to cream with tan iron staining. Luster: Vitreous to waxy. Structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7
Color: Opaque white to cream with tan iron staining
Luster: Vitreous to waxy

Identified July 20, 2026More mineral →

Explore Milky Quartz Pebble in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Mohs hardness: 7. Color: Opaque white to cream with tan iron staining. Luster: Vitreous to waxy. Structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Formation & geological history

Forms in hydrothermal veins or as a constituent in igneous and metamorphic rocks. This specific specimen is a water-worn river pebble, likely millions of years old, shaped by erosion.

Uses & applications

Industrial use as an abrasive, glass making, and as a raw material for silicon. In this form, primarily used for landscaping, aquarium gravel, or as a common collector specimen.

Geological facts

Milky quartz gets its cloudy appearance from microscopic inclusions of fluids or gas trapped during the crystal's growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify by its hardness (will scratch glass), white color, and lack of visible crystal faces due to tumbling. Frequently found in riverbeds, beaches, and glacial till globally.