A rare 1936 German four-rotor K-model Enigma encryption machine was the star of Christie's Science and Natural History Auction in London.
The lot realised £155,000 ($190,030) in the October 19 sale, well above its £90,000 ($110,160) estimate.
The Enigma code was a hugely complex cypher created in Germany in 1918 and used by the Nazis during the second world war.
It was famously cracked by Polish and British intelligence, a breakthrough that dramatically shortened the war.
Christie's comments: "Very few Enigma machines survived the war and it is particularly unusual to find one that was made in the 1930s that remained in such good condition.
"During WWII many of the Enigma machines were destroyed in military actions; near the end of the war the Germans destroyed their remaining Enigma machines as they retreated rather than have them captured by the Allies."
Additionally, Churchill ordered the vast majority of Enigma machines left after the war to be destroyed.
However, some remained in use (particularly in East Germany) as the British government didn't let on that it had broken the code until the 1970s.
A fossilised Rhamphorhyncus muensteri pterosaur achieved £87,500 ($107,275).
The species existed during the Jurassic period (200m-150m years ago).
It was discovered in Solnhofen in Germany. The region is built on limestone that contains an unusually high density of fossils.
Other highlights included a fossil crocodile, also discovered in Germany, that realised £87,500 ($107,275).
While crocodiles survived the great extinction event at the end of the Cretaceous period, they are no longer to be found in Germany (to which Germans should breathe a sigh of relief).
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