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 Hill the Radium and Rare Earth Treatment Company N.L. which continued operations there until 1931. The company also built a treatment plant in 1923 at Dry Creek near Adelaide to produce radium bromide for medical applications from the Radium Hill ore, however this proved to be uneconomic and both sites had ceased operations by 1932. Activity recommenced after World War II, with a Department of Mines geological survey in 1944 and exploration and drilling work done in 1946-1947. In March 1952 the Commonwealth and the South Australian governments signed a cost plus uranium supply contract with the UK-USA Combined Development Agency,