mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent with brown iron staining; Luster: Vitreous to waxy; Crystal Structure: Trigonal (hexagonal system); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to translucent with brown iron staining
Luster: Vitreous to waxy

Identified May 3, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes in veins or within igneous rocks. This specific specimen has been rounded and smoothed by water transport in a river, stream, or coastal environment over thousands of years.

Uses & applications

Milky quartz is used in glass making, as an abrasive, in the production of silicon chips, and for decorative landscaping. Water-worn pebbles are often used in ornamental gardens or for stone tumbling.

Geological facts

The milky white color is caused by tiny inclusions of gas or liquid trapped during the crystal's formation. Quartz is the second most abundant mineral in Earth's continental crust.

Field identification & locations

Identify by its hardness (it will scratch glass), lack of cleavage, and smooth, rounded water-worn texture. It is extremely common in riverbeds and on beaches worldwide.