This is a .36 Caliber two cavity iron mold marked "Colt's Patent" for the Colt Model 1851 Navy Revolver. Overall, the metal has turned to a brown patina with some scattered light corrosion here and there. Both round and conical bullet cavities are in very good shape with no signs of pitting or abuse and if desired, could still produce bullets of excellent quality. Everything is intact including the original Sprue Cutter. Top is marked "Colt's Patent". Nice hinge that is still good and tight with no play. This one will clean up a lot better if desired and would make an excellent companion to an original 51 Navy in good condition.