Corrosion Morphology in Ancient Bronzes- A Study on Decuprification in Bronze Artefacts from Haft Tappeh, Khuzestan, Iran

The Ancient and Historic metallic artefacts have deteriorated due to various environmental factors by different mechanisms over time. Factors such as alloy compositions, microstructure and corrosivity of long-term burial environment influence chemical composition as well as structure of natural patina formed on metal artefacts. Corrosion occurs in metals in different forms and cause different types of corrosion morphology. One of the obvious corrosion mechanisms in bronze artefacts is decuprification or selective dissolution of copper which cause the formation of different corrosion morphologies in ancient copper-tin alloys based on corrosivity of burial environment and corrosion rate.In this paper, some aspects of investigations carried out on selective dissolution of copper in ancient bronzes have been studied. Besides, some bronze artefacts belonging to Haft Tappeh historic site, Khuzestan, Iran, have examined to study decuprification (selective dissolution of copper) process by analytical methods such as SEM-EDS and XRD. The results show effect of decuprification on formation of specific corrosion morphology in these samples.