Ethnographic Arms & Armour - The replica turns out to be the real thing.

Museum discovers its 'replica' sword is actually 3000 years old.

A Hungarian archaeologist declared the replica to be a true Bronze Age sword, and further analysis confirmed this.
For nearly 100 years, the Field Museum of Natural History in Chicago has had a replica of a Bronze Age sword on display. However, this “replica” turned out to be true.
A new analysis of the weapon — which was taken in the 1930s from the Danube River in Budapest, Hungary — has shown that the sword is actually over 3000 years old. When it was found, it was assumed that the sword was a replica possibly made in the Middle Ages or even later.
This assumption held until last year, when the museum was preparing to host an exhibition on ancient European kings and a visiting Hungarian archaeologist declared that the sword was authentic, reports IFLScience.
The museum decided to remove all doubt and went ahead with an analysis that used a fluorescent X-ray detector. To do this, scientists expose the materials they are studying to X-rays in order to ionize them.
If the energy of the radiation is sufficient, then it goes on to interact with the electrons in the inner shell of the atoms, causing them to be expelled. This leads to energy being released in the form of electromagnetic radiation.
By measuring the energy and intensity of X-rays, scientists are able to discover the materials that make up the sword. Analysis has shown that its chemical composition matches that of other artifacts from the same era.
“Usually, this story is the other way around. What we think is original turns out to be fake,” Parkinson says in a press release.

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