Evaluation of atmospheric deposition on historic buildings by combined thermal analysis and combustion techniques

Black crusts collected from monuments and historic buildings were analyzed. The analytical methodology adopted involved a preliminary characterization or the samples by means of X-ny diffraction (XRD). optical microscopy (OM) and scanning electron microscopy (SEM-EDAX). The anions present were quant ified using ion chromatography (IC). Differential thermal analysis (DTA) an d thermogravimetric analysis (TGA), combined with combustion techniques, al lowed the quantification of the products of degradation and atmospheric dep osition. In addition. the carbon of atmospheric origin was identified and q uantified in its carbonate, non-carbonate, elemental and organic fractions. (C) 1998 Elsevier Science B.V.