Yes Neodymium is an element, one of the Lanthanides. And yes it has long
been available for not only experimental work but also industrial work.
It was once used commonly in glass making of specialty colored glasses.
It is now harder to obtain than before. I think because it is considered
to be a strategic element and is therefore being hoarded by governments.
One of its common uses now is in the Neodymium-Iron-Boron super magnets.
These type magnets have virtually the strongest field intensity of any
made.
There is one so-called "element" in Searl's rollers that is in fact not
an element. He claims to use a layer of 'Nylon' and calls it an element.
Also Nylon was new in the '50s. Is that what you are thinking of rather
than Neodymium?