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 mining in Colorado back uranium-mining projects. There are no currently producing uranium mines in Colorado. Hydrothermal uranium deposits are present through a widely spaced area in the Front Range of the Rocky Mountains, in Larimer, Boulder, Gilpin, Clear Creek, and Jefferson counties. The first uranium identified in the USA was pitchblende from the Wood gold mine at Central City, Colorado in 1871. Pitchblende orebodies were also discovered in the Calhoun mine, the Kirk mine, and some others. About 122,000 pounds (55 metric tons) of uranium oxide (UO) were shipped at irregular intervals from six gold mines in the Central City district from 1872