Trancas Geode, Chihuahua Mexico

Trancas geodes may not be as colorful as their coconut cousins, but they put on a lovely show when exposed to short wave UV-light. Characterized by their stunning white drusy crystalline centers, these geodes contain a very small (not harmful) amount of uranium that often fluoresces a brilliant bright-green.

Here you can see one of our geodes turn to a “Green Goddess” after UV light exposure: