Artwork Restoration with the Metrohm Autolab Potentiostat

The «Mother Earth» table decoration by Wenzel Jamnitzer, dating from 1549 and owned by the Rijksmuseum in Amsterdam, has been restored to its former glory with help from a Metrohm Autolab potentiostat.

Wenzel Jamnitzer was a German goldsmith whose work was strongly influenced by Italian Renaissance style. As well as using precious metals, he sometimes incorporated sea shells, coral, snail shells and tiny birds' eggs into his pieces. The replication of miniature plants and animals became a distinctive feature of his oeuvre. And it was these delicate objects that made it impossible to restore his table decoration using the traditional wet chemistry method.

Instead a gentle electrochemical reduction of the silver compounds (tarnished silver) was carried out using an Autolab potentiostat. The potentiostat controls the potential of an electrode mounted in a special electrochemical tool, which is brought into contact with the surface to be cleaned. The negative polarization of the silver metal reduces the silver sulfide to metallic silver.