Marie Curie was present in such minute quantities that they would eventually have to process tons of the ore. In July 1898, Curie and her husband published a joint paper announcing the existence of an element which they named "polonium", in honour of her native Poland, which would for another twenty years remain partitioned among three empires (Russian, Austrian, and Prussian). On 26 December 1898, the Curies announced the existence of a second element, which they named "radium", from the Latin word for "ray". In the course of their research, they also coined the word "radioactivity". To prove their discoveries beyond any
Polonium dioxide reaction of polonium dioxide with potassium hydroxide or potassium nitrate in air gives the colourless potassium polonite (KPoO): Polonium dioxide is closely related to the polonite anion (), similar to the relationship between polonium trioxide and the polonate anion (). Polonium dioxide has no uses outside of basic research. All polonium compounds, such as polonium dioxide, are extremely radioactive and thus must be handled in a glove box. The glove box must further be enclosed in another box similar to the glove box, maintained at a slightly lower pressure than the glove box to prevent the radioactive materials from leaking