Sherr has done a proving with Plutonium nitricum (will be published shortly) in which several themes came up clearly to give us a good overall picture of this remedy.
Plutonium is one of the Actinides, the elements which come after Actinium, the third element in the Uranium series. The Actinides are very similar to Actinium, just as the Lanthanides are very similar to Lanthanum, the third element in the Gold series. We can therefore probably apply the concepts of Stage 3 to the Actinides, and also to Plutonium.
Plutonium is named after Pluto, the God of the underworld, the world of ghosts and spirits. The Greek name for Pluto was Hades. The element was discovered in 1930 and its chemical symbol is Pu.
It is a silvery metal which has 6 different crystalline forms. It is rather reactive and oxidises when exposed to air, forming the yellow coloured plutoniumoxide.
It is also radioactive and the main isotope has a half life of 24360 years. It is usually manufactured artificially in nuclear reactors. It is mainly used to make atom bombs.