A report on the corrosion of the tin sarcophagi of the Austrian Imperial crypt of the Habsburg dynasty during the last 200 years. Even though some of the corrosion looks like tin plague (transformation of tin from a metallic to a powdery state) x-ray and metallographic examinations show that in no case was this present. The tin had corroded to tin oxides, sometimes containing basic copper carbonate from copper alloyed with the tin. Certain experiments and observations on the transformation to grey alpha tin are described.