Discovery of radium Flow Chart of the Major Steps in the Separation and Purification of Radium from Pitchblende Based on Procedure described in Marie Curie's Thesis) Pitchblende ore Crush and treat with sodium carbonate Wash with warm water and dissolve in dilute sulphuric acid Yield: 1 ton: Radioactivity 4 times that of uranium Supernatant contains uranium Residue: Sulphates of Pb, Ca, silica, alumina, iron oxide. small amounts of Cu, Bi, Zn, co, Mn, Ni, Va, Sb, Th, rare Processed for uranium earths, niobidium, Ta, As, Ba, etc. Radium present as sulphate Boil with sodium hydroxide solution to remove sulfuric acid reat with hydrochloric acid 2005-9-13 NECPKU