Radium of radium Curie used the residues after extraction of uranium from pitchblende. The uranium had been extracted by dissolution in sulfuric acid leaving radium sulfate, which is similar to barium sulfate but even less soluble in the residues. The residues also contained rather substantial amounts of barium sulfate which thus acted as a carrier for the radium sulfate. The first steps of the radium extraction process involved boiling with sodium hydroxide followed by hydrochloric acid treatment to remove as much as possible of other compounds. The remaining residue was then treated with sodium carbonate to convert the barium sulfate into
Radium dials loosely referred to as radium jaw. Inhaled or ingested particles may deposit a high local dose with a risk of lung or gastrointestinal cancer due to the radiation dose. The risks are hard to quantify due to the variable levels of radium in the paint and the quantity ingested or inhaled. Care should be taken in handling these materials especially where the paint is damaged. The most common isotope of Radium is Ra, which primarily emits alpha particles. Alpha particles are shielded by most thin materials including paper. However, Ra only emits alpha particles 97 percent of the time with