Uranium mining in the United States 1954 in the Sierra Nevada of Kern County, along the Kern River about northeast of Bakersfield. Two mines, the Kergon mine and the Miracle mine, made small shipments in 1954 and 1955. Uranium occurs as uraninite and autunite in shear zones in granodiorite. Accessory minerals include fluorite and the molybdenum minerals ilsemanite and jordisite. The first uranium identified in the US was pitchblende from the Wood gold mine at Central City, Colorado in 1871. Uranium mining in southwest Colorado goes back to 1898. The Uravan district of Colorado and Utah supplied about half the world's radium from 1910 to 1922,
Uranium ore in the Athabasca Basin region of Canada. Uranium is generally used to generate nuclear fuel. Uranium deposits are generally classified based on host rocks, structural setting, and mineralogy of the deposit. The most widely used classification scheme was developed by the International Atomic Energy Agency (IAEA) and subdivides deposits into 15 categories. 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 U (99.27%) and U (0.72%). All uranium isotopes present in natural uranium are radioactive and fissionable, and U is fissile (will