Protactinium is found mainly in uranium deposits and is highly radioactive and toxic. It does not have many commercial uses due to its instability but is mainly used in research science. It is a by product of nuclear fuel and can be obtained from nuclear fuel rods. It was first identified in 1913 by Kasimir Fajans and Oswald Helmuth Göhring and was given the name brevium due to its short half life. It was not until 1917 that a more stable isotope was found and it was renamed protactinium. Protactinium is one of the rarest and most expensive naturally occurring element and is found in the ore pitchblende. It can also be produced in nuclear reactors and having a half life of 32,760 years means as waste it needs carefully disposing. Whilst not commercially used it has some use in the dating of ice age glaciers due to its long half life. It is a solid metal at room temperature and it has a melting point of 1568°c and a boiling point of 4027°c.
Fredrich Soddy, John Cranston, Otto Hahn, Lise Meitner