Chromium-plated Sword
This sword was found in a bent half-circle shaped when it was unearthed. It was put in storage and one day a researcher came back and discovered the sword had magically became straight. The reseachers decided to test out the sharpness of the sword and found that it could cut through 12 sheets of paper in one slice. They also found that it was chromium-plated---thousands of years before anyone had discovered the technique. According to the tour guide's professor, he believed that aliens had magically rebent the sword back to it's original shape.