History of chemistry element among the fractions that resulted. Working with the mineral pitchblende, the pair discovered a new radioactive element in 1898. They named the element polonium, after Marie's native country of Poland. On December 21, 1898, the Curies detected the presence of another radioactive material in the pitchblende. They presented this finding to the French Academy of Sciences on December 26, proposing that the new element be called radium. The Curies then went to work isolating polonium and radium from naturally occurring compounds to prove that they were new elements. In 1902, the Curies announced that they had produced a decigram
Uranium mining in Colorado granite. Although the zinc skarn and the pitchblende vein are exposed in the same workings, the pitchblende appears to have been deposited much later. Other vein-type uranium mines in the Front Range were the Fairday A. M. mine near Jamestown in Boulder County, and the Wright Lease mine near Ideledale in Jefferson County. The 70 mile long Uravan mineral belt is an arcuate zone of uranium-vanadium deposits in San Miguel, Montrose, and Mesa counties, Colorado, and Grand County, Utah. It was the area most productive of uranium in the United States in the early 20th century. The mineral belt includes