Identification of inorganic pigments from paintings and polychromed sculptures immobilized into polymer film electrodes by stripping differential pulse voltammetry

Inorganic pigments in paintings and polychromed sculptures are studied by c yclic voltammetry and differential pulse stripping voltammetry using micro- sample coatings in Paraloid B72-film modified electrodes. Characteristic ca thodic and anodic differential pulse profiles were obtained in the +0.4 to -1.0 V vs. SCE potential range for different cadmium, copper, lead, mercury and zinc pigments used in traditional colour palettes. Under optimized con ditions, excellent reproducibility was obtained. Microsamples extracted fro m polychromed sculptures, wall paintings, canvas paintings, panel paintings and altarpieces from Spain, Ethiopia and Italy from the 12th to the 20th c enturies have been analyzed and cadmium, copper, lead, mercury and zinc pig ments such as cadmium red cadmium yellow, azurite, copper resinate, malachi te, verdigris, lead-tin yellow, lead white, minium, Naples yellow, vermilio n, chrome orange, chrome yellow and white zinc have been identified by this technique in agreement with PLM, SEM/EDX, XRD and FT-IR analysis. (C) 2000 Elsevier Science B.V. All rights reserved.