Is kryptonite a real mineral on Earth?

A new mineral has been discovered in Serbia with the chemical composition sodium lithium boron silicate hydroxide. This is almost the same as the 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 and is white rather than green, but in all other respects the chemistry matches that for the (fictional) rock containing kryptonite. It's official name is jadarite.

Krypton (symbol Kr, atomic number 36) is one of the noble gases. It forms few compounds, none naturally. If there were such a compound as kryptonite, the name suggests that it should be an ionic compound of the element and oxygen in which the krypton has a lower oxidation number than usual (c.f. sulfate/sulfite, nitrate/nitrite). No such compound exists.

scientificcomputing.com/superman-beware-kryptonite-is.aspx nolonger exists
https://en.wikipedia.org/wiki/Krypton

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Kryptonite is no longer a substance of fiction but something real and existing right here on planet earth. It is not a mysterious substance that arrived on earth from some far off planet however and sadly is in not luminous green

However, the real kryptonite does have the same chemical make up as the kryptonite in the story of Superman according to the scientists who discovered it. The new material was found in a mine in Serbia.

Like the story from the film, 'Superman Returns,' the real kryptonite has a chemical make up of sodium lithium boron silicate hydroxide. The real world kryptonite does lack one component according to a scientist London's Natural History Museum, Dr. Christ Stanley. Stanley said, " The new mineral does not contain fluorine and is white rather than green, but in all other respects the chemistry matches that for the rock containing kryptonite."

Dr. Stanley also said that the earth kryptonite is harmless and that "I'm afraid it's not green and it doesn't glow either - although it will react to ultraviolet light by fluorescing a pinkish orange."

The new material was found in a mine in Serbia by the Rio Tinto a mining company. When the group's mineralogist and geologist first found the new substance they requested some outside help to discover what it was. Three experts two from the National Research Council in Canada were called in when the Rio Tinto group were unable to find a matching known substance. The scientists that investigated the makeup of this new substance were, Dr. Chris Stanley from London and Dr Yvon Le Page and Dr. Pamela Whitfield.

http://sumonova.com/kryptonite-is-real-and-here-on-earth/