well bubba...then take the metal of your choice, go find a pint or two of nitric acid, dump your junk in there and tell me about the purty colors.
what you have done is called an experiment...it mimics in quick time, the same event metal experiences over time in the earth.
now..if this is unacceptable...then google some information on a certain species of German aviator during WWII that could flyover an area and "see" through camouflage...to deathly results for the British.
if those two examples are not enought...well then do read carlos castenada's " the teachings of don juan", gives some great examples of what humans can do with their minds, if they open them.