Darmstadtium

Darmstadtium is element 110. Scientists at the GSI laboratory in Darmstadt, Germany, led by Sigurd Hofmann, made it in November 1994 by fusing nickel nuclei with lead. Earlier attempts at several labs had failed. In 2003 it was named after the city where it was found.

Each atom forms only when two nuclei collide with just the right energy, an extremely rare event, so atoms are made one at a time over days of experiments. They decay within seconds. Its chemistry has never been tested, but sitting below platinum, darmstadtium is expected to behave like a heavy precious metal.