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.

Geologists and mineralogists from mining group Rio Tinto discovered the unusual mineral but, as it didn’t match anything known previously to science, they enlisted the help of mineralogist Dr Chris Stanley at the Natural History Museum. Through his research Dr Stanley, who has named many new minerals in the past, revealed the true identity of the mysterious new mineral: kryptonite.

Dr Stanley comments, ‘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 and is white rather than green, but in all other respects the chemistry matches that for the rock containing kryptonite. We will have to be careful with it – we wouldn’t want to deprive Earth of its most famous superhero!’

The new mineral will be revealed at the Natural History Museum in free events on Wednesday 25 April at 12.30 and Sunday 13 May at 12.30 and 14.30.

Approximately 30–40 new minerals are discovered each year. But before it can be classified as new, a mineral’s chemical properties must be rigorously tested, including its crystal structure. In the case of this new material, the sample’s crystals were too small to be tested through standard techniques. Dr Stanley therefore called in the sophisticated analytical facilities at Canada’s National Research Council (NRC) and the expertise of its researchers, Dr Pamela Whitfield and Dr Yvon Le Page.

‘Knowing a material’s crystal structure means scientists can calculate other physical properties of the material such as its elasticity or thermochemical properties,’ explains Yvon Le Page, an expert in the field of crystallography at NRC. ‘Being able to analyse all the properties of a mineral, both chemical and physical, brings us closer to confirming that it is indeed unique.’ Finding out that the chemical composition of a material is an exact match to an invented formula for the fictitious kryptonite, ‘was the coincidence of a lifetime,’ he adds.

New minerals must be registered with the International Mineralogical Association, the Commission on New Minerals, Nomenclature and Classification. It compares new material against a vast database of all known minerals, to see if the newly discovered rock is genuinely unique.

In addition to the investigative work done by the Natural History Museum and Canada’s National Research Council, scientists from Natural Resources Canada, the Geological Survey of Canada and the Canadian Museum of Nature have collaborated to ensure that the new mineral is recognized by the international scientific community. The mineral will be formally named Jadarite when it is described in the European Journal of Mineralogy later this year.