Polonium the Curies while they were investigating the cause of pitchblende radioactivity. Pitchblende, after removal of the radioactive elements uranium and thorium, was more radioactive than the uranium and thorium combined. This spurred the Curies to search for additional radioactive elements. They first separated out polonium from pitchblende in July 1898, and five months later, also isolated radium. German scientist Willy Marckwald successfully isolated 3 milligrams of polonium in 1902, though at the time he believed it was a new element, which he dubbed "radio-tellurium", and it was not until 1905 that it was demonstrated to be the same as polonium.
Uranium metallurgy to any appreciable extent that is fissile, that is, fissionable by thermal neutrons. The isotope U is also important because it absorbs neutrons to produce a radioactive isotope that subsequently decays to the isotope 239Pu (plutonium), which also is fissile. Uranium in its natural state comprises just 0.71% U and 99.3% U, and the main focus of uranium metallurgy is the enrichment of uranium through isotope separation. Uranium metallurgy In materials science and materials engineering, uranium metallurgy is the study of the physical and chemical behavior of uranium and its alloys. Commercial-grade uranium can be produced through the reduction of