Answered By: Regan Brumagen Last Updated: Jul 19, 2016 Views: 327
Jeb Tomabechi's book "Uranium Glass" states, "Uranium glass, as literally implied , is glass that contains a small amount of uranium added for coloring. The color of the glass is generally classified into two categories, light yellow and light green."
This website by the JUGCC (Japan Uranium Glass Collectors Club) states, "When the uranium atom absorbs the energy of the ultraviolet(UV) rays, it is activated by the UV energy. The atom instantly releases its activated energy as visible light of green color. This green light wavelength (550 nano-meter) is unique to the uranium atom. And its green color can not be changed by anyhow, even if mixing with other color glass. In other words; The fluorescence of vaseline glass is always green. Either red/orange fluorescence or blue/greenish-blue fluorescence means NOT vaseline (or uranium) glass.
Here are some interesting websites.
http://www.glassassociation.org.uk/Journal/uranium.htm (The Glass Association)