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• Composition and extent of deterioration forms on the Nuevo Puente were detected. • Orthophotos acquired by a mobile LiDAR system allowed to quantify the deterioration pattern extent. • Black crust, calcite encrustation and biological colonization patinas were detected by XRD FTIR and optical microscopy. • Black crust and biological colonization exhibited similar reflectance levels. Correctly describing the deterioration patterns is of great importance for the conservation of built cultural heritage. Also, their rapid in situ quantification is an essential requisite when studying exposed stone objects, to define satisfactory restoration actions and to avoid greater damage due to the application of incorrect treatments. The research described in this paper targets developing a methodology to compute the extent of different deterioration patterns on a granitic cultural heritage object using as a case study an overpass bridge called Puente Nuevo in Ourense (NW Spain). The applied methodology consisted of the combination of the geometric and radiometric information collected from a non-invasive and in situ mobile LiDAR system (MLS) and micro destructive analytical techniques. Laser scanning points were used as a base to create orthophotos, being their intensity values the input for an unsupervised classification method to determine the areas occupied for those different deterioration patterns. In parallel, as part of this multi-analytical approach different conventional analytical techniques (X ray diffraction, Fourier transform infrared spectroscopy and optical microscopy) were applied to chemically and mineralogically characterize those deterioration patterns, namely, gypsum black crust, calcite encrustations and biological colonization (mosses). LiDAR technology allowed to determine three different clusters considering the reflectance of those surfaces: uncoated granite, calcite encrustations and black crusts and biological colonization patinas in a combined cluster due to their close reflectance spectra. The computed extent and the location of those deterioration patterns will allow to identify the most suitable cleaning treatment saving money and time. [ABSTRACT FROM AUTHOR]