“…Most of the PGAA data [ 18 , 19 ] reported in the literature are bulk concentrations, and few attempts were made for any spatial or surface-bulk discrimination. Further, the 2D XRF scanning methodology [ 20 , 21 ] is mostly applied to flat shreds [ 22 , 23 , 24 ], while in this work, we attempted to extend XRF scanning to non-flat objects by driving the positioner with a digital mesh geometry obtained by 3D optical scanning.…”