Radium seventh of a gram of radium. One kilogram of the Earth's crust contains about 900 picograms of radium, and one liter of sea water contains about 89 femtograms of radium. Radium was discovered by Marie Sklodowska-Curie and her husband Pierre Curie on 21 December 1898, in a uraninite (pitchblende) sample. While studying the mineral earlier, the Curies removed uranium from it and found that the remaining material was still radioactive. They separated out an element similar to bismuth from pitchblende in July 1898, that turned out to be polonium. They then separated out a radioactive mixture consisting mostly of two
Radium Girls contractor, U.S. Radium was a major supplier of radioluminescent watches to the military. Their plant in Orange, New Jersey, employed over one hundred workers, mainly women, to paint radium-lit watch faces and instruments, misleading them that it was safe. The U.S. Radium Corporation hired approximately 70 women to perform various tasks including handling radium, while the owners and the scientists familiar with the effects of radium carefully avoided any exposure to it themselves; chemists at the plant used lead screens, masks and tongs. U.S. Radium had distributed literature to the medical community describing the "injurious effects" of radium. In spite