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, Minnesota Radium, Minnesota Radium is an unincorporated community in section 19 of Comstock Township, Marshall County, Minnesota, United States. It was built alongside the Minneapolis, St. Paul and Sault Ste. Marie Railroad (Soo Line Railroad) branch line built in 1905 from Thief River Falls, Minnesota, to Kenmare, North Dakota. (This line still operates under the aegis of the Northern Plains Railroad.) The place was named for the element radium. Radium had its own post office from 1905 to 1984. Since 1984, Radium has been served by the post office in Warren. It is also on the Warren telephone exchange and part