The conservation and long-term stabilization of composite artifacts recovered from shipwrecks or submerged archaeological sites remains one of the most difficult problems for object conservators. Holistic conservation strategies are usually required when dealing with complex composite objects. Artifacts that are imbedded in ferrous marine concretions may have corroded together, incorporating foreign materials or small artifacts, and are almost impossible to identify with the naked eye. In these difficult cases, non-destructive identification is necessary using conventional or digital radiographic techniques. In particular, wrought iron artifacts that are subjected to an aggressive marine environment will frequently suffer complete dissolution. A positive of the corroded artifact can usually be made using a molding technique. However, this procedure has rarely been used for a group of tools completely fused together. This paper will present conservation work carried out on composite artifacts recovered from the Porto-Novo shipwreck in 1992. This 1st century A.D. Roman vessel, which was carrying about 138 tons of white marble from Carrara, Italy, was discovered off the coast of Corsica in 1991. During the excavation that took place in 1992, a number of large complex concretions were found between the marble blocks. Examination of the concretions revealed the presence of numerous composite objects including hammers, chisels and a rare set of stone carving tools dating from the 1st century A.D. With the exception of carved or sculpted representations, examples of tools like the hammer head are not known. The techniques used to identify and reveal these artifacts will be presented in detail.