Bullion to B-fields: The Silver Program of the Manhattan Project

Between October 1942 and September 1944, over 14,000 tons of silver bullion bars withdrawn from the U. S. Treasury were melted and cast into magnet coils and busbar pieces for the ``calutron'' electromagnetic isotope-separators constructed at Oak Ridge. Based on Manhattan Engineer District documents, this paper will review the history of this ``Silver Program,'' including discussions of the contractors, production methods, and quantities of material involved.