Radium is an alkaline earth metal that is a silvery white color in its natural solid state. It oxidizes easily in air, and it is extremely radioactive. Radium has an atomic weight of 226, a melting point of 1292 °F, and a boiling point of 3159 °F. Radium used to be used for many commercial purposes in the form of self-luminous paints; once the toxic traits of radium were discovered these uses were quickly stopped. Now, radium is only used for physics experiments and in cancer therapies.