Application of Laser Ablation ICP-MS and traditional techniques to study of black crusts on building stones: a new methodological approach

Introduction In this work, we propose an innovativeapplication of laser ablation inductively coupled plasmamass spectrometry (LA-ICP-MS) as a methodologicalapproach for the chemical characterisation of black crustson stone monuments, associated with traditional micromorphological(optical and scanning electron microscopy)and infrared spectroscopic techniques (FTIR).Methods This new approach was tested on black crustsdeveloping on two marble substrates, one, the columns ofthe San Cosimato cloister in Rome, and the other, asculpture representing an angel, located in Pessano conBornago, a small industrial town near Milan.Discussion The main aim of this study was to develop andtest the reliability of the LA-ICP-MS analytical method onblack crusts and to explore the idea that trace elementconcentrations in black crusts can be applied to investigatetheir origin and the relations between concentrations ofpolluting elements in black crusts and environmentalconditions.Conclusion The results obtained by applying traditionaltechniques find considerable support in the innovativemethod used here, which could determine the concentrationsof a large number of trace elements (including heavymetals) in the black crusts examined, and thus could also beused as a reliable indicator of environmental pollution.