mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Opaque white
Luster: Vitreous to greasy

Identified May 23, 2026More mineral →

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: Opaque white; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

Formed from the crystallization of molten magma or through hydrothermal activity in veins. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth. This specimen has been rounded by fluvial or beach erosion.

Uses & applications

Commonly used as decorative landscaping stone, in glassmaking, as an abrasive, and sometimes in low-cost jewelry or as a healing stone in metaphysical practices.

Geological facts

Quartz is the most abundant mineral in the Earth's continental crust. Milky quartz specifically gets its 'milkiness' from millions of microscopic bubbles that were trapped as the crystal grew billions of years ago.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), its lack of cleavage, and its characteristic waxy or sugary white appearance. It is found globally in riverbeds, beaches, and mountain terrains.