Elemental analysis of geological materials: A review of XRF, LIBS, ICP-OES, ICP-MS, and AAS

Selecting an analytical technique for characterization of geologic material is a trade-off in sensitivity, elemental coverage, portability, and cost. This review discusses five important analytical techniques used in geochemistry: X-ray fluorescence (XRF) spectrometry, laser-induced breakdown spectroscopy (LIBS), inductively coupled plasma optical emission spectroscopy (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and atomic absorption spectroscopy (AAS). Laboratory-based methods such as AAS remain the most accessible option for routine single-element analysis of metals and metalloids. ICP-OES enables multi-element analysis with high sample throughput and broad linear dynamic range that AAS cannot match. It offers higher sensitivity in the ppb to sub-ppb range, though it requires extensive sample preparation procedures (acid digestion). ICP-MS extends this sensitivity into the sub-ppt range and adds isotopic analysis. Portable XRF (pXRF) and LIBS (hLIBS) devices allow near-real-time on-site measurements with minimal sample preparation but have higher detection limits. Thus, no single method satisfies every analytical requirement. Important trends shaping the future of these techniques include the development of downhole LIBS probes, emerging hybrid instruments combining multiple detection principles, and machine learning methods that automate spectral deconvolution and analysis. This review highlights the analytical capabilities and limitations of each technique, with particular emphasis on detection limits, elemental coverage, sample preparation, cost, and portability. Thus, it provides a useful framework to select the most appropriate analytical technique for specific geochemical applications.