Chemical characterisation is rough: the impact of topography and measurement parameters on energy-dispersive X-ray spectroscopy in biominerals

Abstract Energy dispersive X-ray microscopy (EDX) is a widely available, inexpensive method of characterizing the in-situ elemental composition samples in Earth and life sciences. Common protocols textbooks focussing on material sciences address EDX analysis metallic that can be polished perfectly, whereas geoscientists often investigate specimens with prominent topography composed light, difficult to resolve elements. This further compounded by scarcity literature surrounding methodology SEM–EDX field palaeontology, leading common misinterpretations artefacts during data acquisition. Here, errors obtained arising from surface parameters subject user decisions are quantified. As model, fossil bioapatite (conodonts) abiotic Durango apatite used. It shown even microscale distort measured up 34%, topographic features such as tilt respect electron beam lead differences 85%. Working distance was not most important parameter affecting results led 13%, choice standard its levelling sample inaccuracy reaching 33%. also affected damage effects acceleration voltage acquisition resolution An estimate provided severity associated which cannot satisfy preparation requirements for fully, holotypes, decisions. Using palaeontological example, recommendations offered best relative importance error sources assessed.