Returning a 300-year-old cannon to its former glory: an insight into our materials conservation departmentVideo | Updated 3 years ago After a long period of time spent underwater, sometimes more than three centuries, metal artefacts undergo critical transformations. Over time they become covered in corrosion products and start rusting. It belongs to the Western Australian Museum to preserve this historic metalwork and, thus, preserve the State’s scientific and cultural heritage. In this video conservator Jon Carpenter is talking about the methods employed by the Materials Department of the Museum to clean up and stabilise cannons excavated off the Western Australian coast. View the discussion thread.