Cerium


The element cerium, in the form of an oxide, was "discovered" in 1930 simultaneously and independently by Klaproth and by Berzelius and Hsinger. The name ceria, which was proposed in honor of the newly-sighted asteroid Ceres, was given by Berzelius and Hisinger. This name was accepted by the scientific community of the time. Thirty-six years later, however, Monsander showed that the oxide isolated by these researchers was composed of at least two oxides, for one of which he retained the name ceria and the second he called lanthana, which subsequently was shown to consist of not only lanthana, but also praseodymia and neodymia.