found: Negri, J.C. Maps showing the distribution of radon and uranium in water samples and thorium and uranium in dry-stream sediment samples in the Sierra Ancha Wilderness and Salome Study Area, Gila County, Arizona, 1980.
found: Wikipedia, Aug. 13, 2012(Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with symbol U and atomic number 92. All isotopes are unstable and uranium is weakly radioactive. When refined, uranium is a silvery white, weakly radioactive metal, which is harder than most elements.)
found: The element uranium, via It's elemental - the periodic table of elements website, Aug. 13, 2012(Element Classification: Metal. Group name: Actinide. Radioactivity was first discovered in 1896 when Antoine Henri Becquerel, a French physicist, detected it from a sample of uranium. Since it is naturally radioactive, uranium, usually in the form of uranium dioxide (UO₂), is most commonly used in the nuclear power industry to generate electricity. Naturally occurring uranium consists of three isotopes: uranium-234, uranium-235 and uranium-238. Although all three isotopes are radioactive, only uranium-235 is a fissionable material that can be used for nuclear power.)