Quantification of Lithium and Mineralogical Mapping in Crushed Ore Samples Using Laser Induced Breakdown Spectroscopy

Abstract

This article reports on the quantification of lithium and mineralogical mapping in crushed lithium ore by laser-induced breakdown spectroscopy (LIBS) using two different calibration methods. Thirty crushed ore samples from a pegmatite lithium deposit were used in this study. Representative samples containing the abundant minerals were taken from these crushed ores and mixed with resin to make polished disks. These disks were first analyzed by TIMA (TESCAN Integrated Mineral Analyzer) and then by a LIBS ECORE analyzer to determine the minerals. Afterwards, each of the thirty crushed ore samples (<10 mm) were poured into rectangular containers and analyzed by the ECORE analyzer, then mineral mapping was produced on the scanned surfaces using the mineral library established on the polished sections. For the first method the lithium concentrations were inferred from the empirical mineral chemistry formula, whereas the second one consisted of building a conventional calibration curve with the crushed material to predict the lithium concentration in unknown crushed materials.

Laser-Induced Breakdown Spectroscopy Imaging for Material and Biomedical Applications: Recent Advances and Future Perspectives

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“…First, different locations are prospected, and mineral cores are extracted and sent to laboratories for analysis. Preconstructed setups can provide sensitive results in the range of ppm, with a resolution ranging from 40 to 200 μm according to the core size, at a high speed of analysis . The major strengths of such setups from Elemission are the speed of analysis and the ability to conduct scanning directly on the drill core.…”

“…The global elemental composition is then retrieved afterward using complementary analytical approaches, such as XRF or ICPbased analysis, and then used to calibrate the imaging experiments in a semiquantitative approach. Several examples of using this strategy, such as those involving Ti-doped sapphire, 65 lithium ore, 29 copper−nickel ore, 31 murine kidney, 66 or heterogeneous catalysts, 67 have been reported. In other cases, additional imaging techniques may be applied to calibrate the LIBS measurements.…”