675 Research Article Received: 6 September 2009 Revised: 12 December 2009 Accepted: 11 January 2010 Published online in Wiley Interscience: 23 April 2010 (www.interscience.wiley.com) DOI 10.1002/sia.3258 Tailored analytical strategies for the investigation of metallic artefacts from the Ayanis Fortress in Turkey † E. Angelini, a* A. Batmaz, b A. Cilingiroglu, b S. Grassini, a G. M. Ingo c and C. Riccucci c A noteworthy number of metallic artefacts dating back to 673–645 BC have been found during excavations in the Ayanis Fortress, near the lake of Van. They are large bronze shields, quivers, helmets, arrows and plates, some of which are decorated with cuneiform inscriptions, and demonstrate a high-level quality of technological competence reached by the ancient craftsmen of Ayanis during the reign of King Rusa II. The artefacts have been studied from a microchemical, micromorphological and microstructural point of view by means of different techniques, from optical microscopy to scanning electron microscopy (SEM), to X-ray diffraction. Microchemical and microstructural investigations showed metallurgical features of the bronze artefacts and of the corrosion products’ layered structures that can be explained in terms of manufacturing processes (repeated cycles of mechanical work and annealing thermal treatments) and environmental context (presence of high amounts of chlorides in the soil that preferentially attack the bronze along the grain boundaries). In particular, the repeated cycles of mechanical work and annealing thermal treatments were carried out to restore the ductility and the malleability of the alloy, thus inducing the crystallisation and the growth of flattened grains as well as impurities segregation phenomena along grain boundaries. Copyright c  2010 John Wiley & Sons, Ltd. Keywords: corrosion; bronze artefacts; cultural heritage; SEM/EDS; metallography Introduction Conservation and valorization of cultural heritage is a fundamental element and an essential mission of Mediterranean countries where the major part of the ancient artistic and fascinating witnesses of the human art and creativity are conserved. The European Community projects of the V and VI Framework Program, in particular, the INCOMED projects EFESTUS and PROMET, were an occasion for exploiting the research potential of a multidisciplinary network of material scientists and conservators belonging to different institutions devoted both to research and to conservation. This paper deals with some results of a wide study performed on metallic artefacts coming from the Ayanis Fortress, in order to improve the capacity of the artefacts to withstand any of the natural or human-generated degradation process, to ameliorate the perception of their morphological features and to perceive their aesthetic, stylistic and documentary message. The Ayanis Fortress was built 35 km north of the modern town of Van in Turkey, on a rocky hill near the village of Agarti on the eastern shore of the Van Lake, by Rusa II, a king of the Urartian Kingdom who ruled between 680 and 640 BC, Fig. 1(a). The citadel was constructed just after 673–672 BC The archaeological excavation at the fortress, started in 1989, indicate two main occupation levels, Medieval and Iron Age II. The Medieval occupation belongs to the 10th or 11th century AD, according to two Byzantine coins recovered from the site. [1] The fortification walls on the south slope are the most monumental architectural features of the fort. Of particular historical interest, flanking the entrance to the temple is the presence of the longest inscription (16 m), of the Urartian history, after the one on the Horhor Royal tomb. The inscription describes the activity of King Rusa II, who took slaves from the countries Hate, Mushki and Assyria and built for them a city and a garden around the fortress. [2] A huge amount of metallic artefacts of copper-based and iron- based alloys, such as nails, spear heads, arrow heads, shields, helmets and swords were found during the excavations in the various areas of the fortress. As an example, Fig. 1 (b) shows a shield found in the storage rooms of the temple area in 2001, with an inscription dedicated to God Haldi. In order to solve the problems faced by the conservators in the safeguarding of the metallic artefacts, a multidisciplinary approach has been adopted for their investigation with the ultimate goal of finding proper conservation procedures. Several copper-based and iron-based metallic artefacts were studied from a microchemical, micromorphological and mi- ∗ Correspondence to: E. Angelini, Department of Materials Science and Chemical Engineering, Politecnico di Torino, 10129 Torino, Italy. E-mail: emma.angelini@polito.it † Paper published as part of the ECASIA 2009 special issue. a Department of Materials Science and Chemical Engineering, Politecnico di Torino, 10129 Torino, Italy b Department of Protohistory and Near Eastern Archaeology, Ege University, 35040 Bornova-Izmir, Turkey c Institute for the Study of Nanostructured Materials, National Research Council, 00016 Monterotondo Stazione, Rome, Italy Surf. Interface Anal. 2010, 42, 675–679 Copyright c  2010 John Wiley & Sons, Ltd.