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 from anemia, bone fractures and necrosis of the jaw, a condition now known as radium jaw. It is thought that the X-ray machines used by the medical investigators may have contributed to some of the sickened workers' ill health by subjecting them to additional radiation. It turned out at least one of the examinations was a ruse, part of a campaign of disinformation started by the defense contractor. U.S. Radium and other watch-dial companies rejected claims that the afflicted workers were suffering from exposure to radium. For some time, doctors, dentists, and researchers complied with requests from the companies not