This image was created by placing a slice of radioactive uranium ore conglomerate on a sheet of sensitive x-ray film for four days. The brightest spots represent the highest sources of radiation. Color then was applied to the black and white image. The conglomerate (also called pitchblende) is from Ontario, Canada. It is made up of uranium (U) and oxygen (O) in the chemical formula U3O8. The ore is important for the nuclear industry as a source of uranium.