'Superman’s nemesis, kryptonite, is no longer the stuff of fiction. A new mineral matching its unique chemistry - as described in the film Superman Returns - has been identified by scientists at the Natural History Museum and Canada’s National Research Council.
'Kryptonite’s devastating power is the bane of Superman stories, where exposure to its large green crystals causes the superhero to weaken dramatically. Unlike its famous counterpart however, the new mineral is white, powdery and not radioactive. And, rather than coming from outer space, the real kryptonite was found in Serbia.' (Science Daily article).
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