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Amagnet's a magnet, no matter what it's made out of. Neodymium ones simply tend to be much stronger compared to ceramic ones, and electromagnets aren't permanent, but if you can get a nice one would be even stronger.
Then there's more chance for the stuff to come out of the top. If you just want to play around a bit, just pour it in the tray and use a pipette to get it out. But if you want something like a desk toy, you probably want a glass jar with a lid.