Selective Electrochemical Treatment of Naturally Aged Silver Alloy Artefacts

Abstract

Conservation interventions on silver tarnish and corrosion layers include mechanical, chemical, and electrolytic techniques. Electrolytic reduction is still disputed among metal conservators. The prevailing conviction with many is that mechanical cleaning methods are more likely to maintain control over the result than electrochemical methods. A survey on this subject undertaken in Germany and Austria suggested that this may be due to the traditional approaches of academic education. An electrolytic pencil was further developed and has been applied on naturally aged silver artefacts of the nineteenth and twentieth centuries. The influence of the electrochemical potential difference between artefact and counter electrode as well as of the tip diaphragm material was evaluated. A minimized material loss and a good controllability of conservation interventions on silver alloys were demonstrated.