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 trioxide which operates at the world's largest uranium refinery at Blind River, Ontario, produces high-purity uranium trioxide. It has been reported that the corrosion of uranium in a silica rich aqueous solution forms uranium dioxide, uranium trioxide, and coffinite. In pure water, schoepite (UO)O(OH)·12(HO) is formed in the first week and then after four months studtite (UO)O·4(HO) was produced. This alteration of uranium oxide also leads to the formation of metastudtite, Like all hexavalent uranium compounds, UO is hazardous by inhalation, ingestion, and through skin contact. It is a poisonous, slightly radioactive substance, which may cause shortness of breath, coughing, acute