Flash Rocks

What would Flash Gordon think? Is that triboluminescence in your pocket, or are you just happy to see us? Forseriously though... Just rub our Flash Rocks together to see a totally natural piezoelectric rock show! They'll glow internally and emit a distinctive odor! If you're lucky... someday soon you will be holding electric potential in your hands, so you can see for yourself. Flash rocks - aka quartz - are one of the few minerals with piezoelectric proprieties. So, when subjected to mechanical stress, these two little rocks generate an electrical charge. Just place a rock in each hand, and forcefully rub the rocks together. To see the glowing electrical effect fully, you should do this in a darkened room. Also, note the distinctive odor given off by the frictions. Made in the USA. Stone size varies. Card measures 3.5 inches wide x 6 inches long.