Uranium mining in Colorado the Slick Rock, Gypsum Valley, Uravan, and Gateway mining districts. Uranium mining in southwest Colorado goes back to 1898, when a miner dug ten tons of yellow ore that tested high in uranium and vanadium out of a deposit at Roc Creek in Montrose County, Colorado, and shipped it to France, where M. M. C. Friedel and E. Cumenge identified the new mineral that they named carnotite. The mineral was mined for its vanadium, with uranium as a byproduct. Although radium had been discovered in 1898, it had been derived from pitchblende, and the radium content of carnotite was not
Peak uranium amount of energy to be produced per mass unit of uranium, because U-238, which constitute 99.3% of natural uranium, is not used in conventional reactors which instead use U-235 which only represent 0.7% of natural uranium. In 1983, physicist Bernard Cohen proposed that the world supply of uranium is effectively inexhaustible, and could therefore be considered a form of renewable energy. He claims that fast breeder reactors, fueled by naturally-replenished uranium-238 extracted from seawater, could supply energy at least as long as the sun's expected remaining lifespan of five billion years., making them as sustainable in fuel availability terms as