1. Education

Glowing Radium Dial

By

This is a glowing radium painted dial from the 1950s.

This is a glowing radium painted dial from the 1950s.

Arma95, Creative Commons License
Radium mixed with copper-doped zinc sulfide produces a paint that will glow in the dark. The radiation from the decaying radium excited electrons in the doped zinc sulfide to a higher energy level. When the electrons returned to the lower energy level, a visible photon was emitted.

©2014 About.com. All rights reserved.