CT scans of a 16th century sword from Jena in Germany have revealed a name engraved on the blade, hidden by a thick encrustation of rust. The inscription reads Clemes Stam, the name of the Solingen swordsmith who made it.The blade was one of four surviving swords interred in the graves of the Collegiate Church in Jena where faculty, students and their families were buried in crypts between the late 16th and early 19th centuries. The church was destroyed by an allied bomb at the end of World War II, and the four swords were recovered from the rubble.For seven years, researchers at the University of Jena have been analyzing the objects recovered from the Collegiate Church. Archaeologist Enrico Paust suspected there might be an inscription, but did not have the technology to penetrate the heavy corrosion layer to see inside to the blade, which is larger than the usual sample. He enlisted the aid of industrial research institution INNOVENT e.V. to virtually break through the barrier.The EasyTom 150-160 X-Ray Micro& Nano-CT computed tomography scanner from the French manufacturer RX Solutions, available at INNOVENT since the end of 2022, represents a good compromise between sample size and resolution.On the one hand, relatively large samples up to 70 cm in height can be measured; on the other hand, a relatively high resolution (voxel size <1 m) is possible, as is necessary, for example, for examining circuits.The rapier did indeed fit into the sample chamber, raising hopes that the rapier could be virtually unwrapped from the corrosion layer and a potential inscription revealed.The scan was able to peel back the encrustations in layers, first revealing the remains of a sheath on the blade. Under the sheath, imaging revealed evidence that the blade had been manufactured by welding different types of steel together. The inscription was then inlaid into the blade steel with individually crafted letters made of copper sheeting just 0.6 mm thick.Comparable weapons from the period 1580 to 1620 can be found in the German Blade Museum in Solingen. Weapons of this type could and were only permitted to be carried by members of the upper class. The Solingen workshop supplied the European high nobility with exclusive weapons and also crafted weapons for the Spanish king. The Jena rapier stands out from weapons with stamped inscriptions due to its elaborate inlay work.Such a rapier in Jena could only have belonged to a rector or a student of noble birth.