LIBS; Microscopy; Compositional mapping; 3D analysis; DP-mu LIBS; Euro coins;PLASMA-MASS SPECTROMETRY; LIBS

In this communication, we present the development of the first double-pulse micro-LIBS (DP-mu LIBS) instrument for three-dimensional compositional mapping of materials. The system allows for high-resolution three-dimensional scanning of materials; its advantages with respect to conventional single-pulse micro-LIBS systems are described and discussed. As a test example, we analyzed three Euro coins to show the performances of the system on homogeneous samples (20 Eurocents), heterogeneous samples (1 Euro) and layered samples (5 Eurocents). DP-LIBS cannot provide isotopic information and has, typically, limits of detection for the elements of interest much higher with respect to Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (IA-ICP-MS). However, when the isotopic information and the extreme sensitivity to trace elements is not be necessary, the results obtained show that DP-mu LIBS can be a viable alternative to LA-ICP-MS for the acquisition of high resolution threedimensional compositional maps. (C) 2016 Elsevier B.V. All rights reserved.