N'afọ 1940, e nwere ebe anọ a maara nke ọma nke uranium: na Colorado, n'ebe ugwu Canada, na Joachimsthal na Czechoslovakia, na na Belgian Congo. Ihe niile ma Joachimstal nọ n'aka ndị Allied. Nnyocha e mere na November 1942 gosiri na e nwere uranium zuru ezu iji gboo ihe ndị a chọrọ n'ọrụ ahụ. Nichols mere ndokwa na Ngalaba Na-ahụ Maka Ọchịchị maka mbupụ mbupụ ka a na-etinye na uranium oxide ma kwurịta maka ịzụta obere oge 1,200 tọn (1,100 t) nke uranium ore site na Belgian Congo nke a na-echekwa na ụlọ nkwakọba ihe na Staten Island ma na-echekwa ihe ndị fọdụrụnụ nke ore ore na-echekwa na bọmbụ atọm n'onwe ya.
Afọ 1942