http://news.bbc.co.uk/1/hi/sci/tech/6584229.stmKryptonite is no longer just the stuff of fiction feared by caped superheroes.
A new mineral matching its unique chemistry - as described in the film Superman Returns - has been identified in a mine in Serbia.
"Towards the end of my research I searched the web using the mineral's chemical formula - sodium lithium boron silicate hydroxide - and was amazed to discover that same scientific name, written on a case of rock containing kryptonite stolen by Lex Luther from a museum in the film Superman Returns.
"The new mineral does not contain fluorine (which it does in the film) and is white rather than green but, in all other respects, the chemistry matches that for the rock containing kryptonite."
The mineral cannot be called kryptonite under international nomenclature rules because it has nothing to do with krypton - a real element in the Periodic Table that takes the form of a gas.