Uranium is a silvery-gray metallic weakly radioactive chemical element. It has the chemical symbol U and atomic number 92. The most common isotopes in natural uranium are 238 U (99.27%) and 235 U (0.72%).
Uraninite and masuyite are the major uranium minerals, essentially fine grained, in the ores studied. Over 40% of the uranium is distributed in the -8µm fractions compared with copper, which is concentrated mainly in the +8-20µm range.