Marie Curie doubt, the Curies sought to isolate polonium and radium in pure form. Pitchblende is a complex mineral; the chemical separation of its constituents was an arduous task. The discovery of polonium had been relatively easy; chemically it resembles the element bismuth, and polonium was the only bismuth-like substance in the ore. Radium, however, was more elusive; it is closely related chemically to barium, and pitchblende contains both elements. By 1898 the Curies had obtained traces of radium, but appreciable quantities, uncontaminated with barium, were still beyond reach. The Curies undertook the arduous task of separating out radium salt by differential
Operation Sandstone firings. More efficient weapons would require less efficient initiators. This meant that less polonium would be required. At the time of Sandstone, the national stockpile of polonium-beryllium initiators consisted of 50 A-Class initiators, with more than 25 curies of polonium, and 13 B-Class initiators with 12 to 25 curies. During Sandstone, at least one test would be conducted with a B-Class initiator. The tests were authorized by President Harry S. Truman on June 27, 1947. The Atomic Energy Commission's Director of Military Applications, Brigadier General James McCormack and his deputy, Captain James S. Russell, met with Bradbury and John Manley