Flash Rocks

Flash rocks, also known as quartz, are piezoelectric rocks! They are one of the few minerals with properties that will create an electrical charge when subjected to mechanical stress. 

Put 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. Please note: they do give off a distinctive odor from the friction. Do not hit the rocks together, just rub! 

* Do not hold close to eyes while performing the experiment!