mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 Mohs; Color: White to translucent; Luster: Vitreous/Waxy; Crystal Structure: Trigonal/Hexagonal (usually obscured in water-worn pebbles); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 Mohs
Color: White to translucent
Luster: Vitreous/Waxy

Identified May 7, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Formed from hydrothermal solutions or cooling magma where gas bubbles or inclusions of fluid/gas were trapped during crystallization, creating the cloudy appearance. Often found in riverbeds as water-tumbled erosion products.

Uses & applications

Used in glassmaking, as an abrasive, in electronics (though usually higher purity quartz), as decorative landscaping stone, and in meditation/spiritual practices.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Its white color is caused by tiny fluid inclusions of gas and/or liquid trapped during crystal growth.

Field identification & locations

Identify by its hardness (cannot be scratched by a steel nail), white color, and smooth, rounded surface if found in river/beach environments. Found globally in almost all rock types and environments.