Real “Kryptonite”
From the BBC, real “Kryptonite” is found in a mine in Serbia, with the chemical name “sodium lithium boron silicate hydroxide”. Apparently, in “Superman Returns,” that was the name of the rock with kryptonite that Lex Luthor stole.
Too bad it can’t officially be named “Kryptonite”, considering it has no krypton (the noble gas) in it.
