Hassium

Hassium is element 108. The GSI laboratory in Darmstadt, Germany, made it in 1984 by fusing iron nuclei with lead. Its name comes from Hassia, the Latin name for Hesse, the German state where the lab sits.

Like other superheavy elements, it is made only a few atoms at a time, and each atom decays within moments. In 2001 chemists turned a handful of hassium atoms into a volatile oxide, HsO₄, just as osmium, the element above it, forms osmium tetroxide. That made hassium the heaviest element whose chemistry had been studied at the time. Theory predicts that bulk hassium would be one of the densest substances of all, if enough could ever be gathered.