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 dichloride red solution followed by a flaky white precipitate of unknown composition. Polonium dichloride Polonium dichloride is a chemical compound of the radioactive metalloid polonium and chlorine. Its chemical formula is PoCl. Polonium dichloride appears to crystallise with an orthorhombic unit cell in either the "P"222, "P"mm2 or "Pmmm" space group, although this is likely a pseudo-cell. Alternatively, the true space group may be monoclinic or triclinic, with one or more cell angles close to 90°. Assuming the space group is "P"222, the structure exhibits distorted cubic coordination of Po as {PoCl} and distorted square planar coordination of Cl as {ClPo}.