Electrochemical identification of bronze corrosion products in archaeological artefacts. A case study

摘要

The electrochemical response of the products of bronze corrosion is studied upon sample attachment to paraffin-impregnated graphite electrodes immersed into phosphate buffer. Characteristic square wave voltammetic profiles were obtained for CuCO₃, CuCl, Cu₂O, CuCl₂ · 2H₂O, azurite, malachite, atacamite and clinoatacamite. Application to real microsamples from a montefortino bronze helmet from Requena (Valencia, Spain) dated back to the Second Iron Age reveals the presence of different corrosion products, namely, cuprite, nantokite, and atacamite-type materials. Data obtained from voltammetric and energy dispersive X-ray microanalysis in the samples extracted from different corroded zones of the helmet were in good agreement.