The Acqualadrone Rostrum: a physical-chemical investigation to understand the Material History

The aim of this work is to define the conservation state and to ascertain theprovenance of raw materials used in the construction of the AcqualadroneRostrum. In 2008 the rostrum (an offensive naval weapon mounted on the prow atthe waterline), from an ancient warship was recovered from the Mediterraneannear Acqualadrone, Messina, Sicily. The archaeological discovery has led to theneed for scientific research in order to plan the conservation treatment of thisartefact. The discovery is exceptional because of the presence of a wooden sectionfrom the original ship.The physical-chemical investigation, by using some complementary spectroscopictechniques, was focused on the characterization of both the metal alloy and thewooden fragments.The results reveal the use of leaded bronze (Cu, 70%; Pb, 20%; Sn, 10%) in themanufacturing process of the alloy and the use of lead whose isotopic compositionis referable to either Spanish or Cypriot mines.The analysis of the results relating to the wooden samples indicates constructionfrom pinewood. A derivatized extract of black wood yielded forms of abietic acidand sandaracopimaric acid consistent with pine pitch waterproofing. In summary,the rostrum was manufactured of pine wood and subsequently waterproofed withpine pitch.The subsequent 2300 years included battle, foundering, and marine burialfollowed by anoxia, bacterial colonization, sulfate reduction, and mobilization oftransition metals, which produced pyrite and copious appended sulfurfunctionality.Furthermore a quantitative determination and the cristallinity degree evaluation ofthe holocellulose were performed through solid state NMR on a wooden sampleobtained by coring.Finally results obtained by solid state NMR relaxometric experiments and 2Dheterocorrelated analyses will be the subject of a forthcoming work.