http://news.yahoo.com/s/ap/20070424...e_discovery;_ylt=AltXlnm8xmK0P0y1_dW5NeXMWM0F
New mineral has kryptonite composition
LONDON - A mineral recently discovered in Serbia has the same composition as kryptonite the fictional substance that robs Superman of his powers the British Museum said Tuesday. While the material is not a perfect match, its chemical breakdown is strikingly similar.
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"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 Luthor from a museum in the film 'Superman Returns,'" Stanley said.
The material is white, powdery and not radioactive unlike the glowing green crystals usually depicted in the Superman comics. It will be formally named Jadarite when it is described in the European Journal of Mineralogy later this year.