Radium bromide Institute had four grams of radium total, which at the time was more than half the world supply. Countries all over the world set out to make as much radium as possible, a time consuming and expensive task. It was reported in "Science" magazine in 1919 that the United States had produced approximately 55 grams of radium since 1913, which was also more than half the radium produced in the world at the time. A principal source for radium is pitchblende, which holds a total of 257 mg of radium per ton of UO. Obviously with so little product recovered
Radium bromide concentrate the radium as a combination of radium and barium. This is done by treating the ore with a barium salt and sulfuric acid which help the uranium, iron, copper, and other components become soluble. A residue containing gangue, barium, radium, and lead sulfates will be left over. The mixture will then be treated with sodium chloride to remove lead and convert radium and barium into carbonates that are insoluble in hydrochloric acid. The second step requires fractional crystallization to separate the barium from the radium. Because of the differences in solubility between radium and barium in bromide or chlorine,