An Investigation into the Impact of Sealed Wooden and Acrylic Showcases and Storage Cases on the Corrosion of Lead Objects during Long Term Storage and Display

Abstract

Three case studies are presented which demonstrate the effects of long-term build-up of volatile organic compounds (VOCs) on metallic lead in sealed environments. In the first case study, severe lead corrosion was found on an object within a wooden storage case which had been unopened for more than 2 years. In the other two case studies, corroded lead objects were discovered in two showcases which were left unopened for more than a decade. In the showcases the corrosion occurred after an extended incubation period that suggested that the VOCs must accumulate until they reach a critical concentration after which point corrosion occurs rapidly. X-ray diffraction was used to identify the lead corrosion products as lead formate [Pb(HCO2)2] and hydrocerussite [Pb3(CO3)2(OH)2].