n a mineral consisting of uranium oxide and trace amounts of radium and thorium and polonium and lead and helium; uraninite in massive form is called pitchblende which is the chief uranium ore
The Belgian pitchblende mines, whence the related radium, polonium and lead are refined, are at Katanga, Belgian Congo.
The Turkestan samples of pitchblende (the main source of radium) run almost twice as high in radium content as the Congo ores, and will make possible its distribution in America .
They carry the pitchblende to the surface in crude buckets attached to winches.