Elemental Characterization of Iron Meteorites Solely Based on LA-ICP-MS

Chemical composition is an essential aspect of classifying iron meteorites. In this study, we developed and validated a stand-alone procedure for the chemical characterization of iron meteorites using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The adopted innovative approach to the analytical sequence included new features in data reduction software, such as external calibration with more than one measurement standard, yield corrections, and normalization for matrix elements. The obtained results of As, Au, Co, Cr, Cu, Fe, Ga, Ge, Ir, Ni, Os, Pd, Pt, Re, Rh, Ru, and W in nine known iron meteorites agreed with the published values, their recognized chemical classifications, and distribution on normalized chondrite diagrams. Moreover, the results obtained closely correlate with those employed to classify three Brazilian iron meteorites (Conceicao do Tocantins─H, IIAB; Nova Olinda─Ogg, IIAB; and Augusto Pestana─Og, IIIE), which have recently been included in the Meteoritical Bulletin Database. Additionally, we illustrate that LA-ICP-MS elemental mapping, conducted within regions featuring diverse phases of the Augusto Pestana meteorite, serves as a potent tool for chemical classification even without prior knowledge regarding natural structural variations.