Conservation of An Actively Corroding Rare Copper-based Object from The Museum of Jordanian Heritage, Jordan

Abstract

Copper-based artefacts excavated from high chloride burial environments can develop destructive cyclic corrosion known as the bronze disease when exposed to uncontrolled humidity and oxygen. This research deals with the corrosion behaviour and conservation of a rare Ayyubid Mamluk copper cauldron used for boiling sugar syrup for sugar production in the Jordan Valley. The object was kept in the Museum of Jordanian Heritage storage area for about ten years under uncontrolled and unfavourable climatic conditions. The object developed active corrosion, which threatens its existence. This study aims to preserve the object by implementing proper conservation interventions based on the diagnosis of the corrosion behaviour of the object. Analytical techniques including ICP-OES, X-Ray Diffraction, Optical Microscopy, and Metallographic examinations were used to determine the object chemical composition, manufacturing technology and corrosion behaviour. The object was treated using a multi-step conservation process that included mechanical cleaning, treatment with benzotriazole, protective coating and the creation of a controlled microclimate. Its conservation enabled the transfer of the cauldron from being stored to being exhibited.

Keywords

• copper cauldron
• sugar production
• jordan valley
• ayyubid-mamluk period
• bronze disease
• benzotriazole