That is an apt description since lanthanum generally occurs along with other so-called rare earth elements and is very difficult to separate. The abundance of the metal is similar to that of zinc or nickel. The pure metal is silvery white and malleable. It is soft enough to cut with a knife and will oxidize readily in the air as well as react with moisture. For that reason the metal is usually stored under oil or kerosene.
Most lanthanum is extracted from monazite sands .
It was discovered by Debierne in 1899 and again in 1902 by Giesel. Eventual priority was given to Debierne's work. Samples of actinium quickly decay to thorium and francium. The element is obtained as an impurity in pitchblende, an ore mined for its uranium content.