POTASSIUM DETERMINATIONS USING SEM, FAAS AND XRF: SOME EXPERIMENTAL NOTES

Abstract

The calibration of Scanning Electron Microscopy coupled with Energy Dispersive X- Rays Spectrometry (SEM-EDS) for elemental quantitative analysis is an important task for characterization, provenance and absolute dating purposes. In particular the potassium determination is an important contributor to dose rate assessments in luminescence and Electron Spin Resonance (ESR) dating. Here a SEM-EDX is calibrated on different archaeological and geoarchaeological materials against standard laboratory samples as well as measured by micro X-Rays Fluorescence (μXRF) and flame atomic absorption spectroscopy (FAAS) techniques. A common linear relationship is obtained for most elements and certain rock types used and two clear linear regressions for two types of rocks; one for granite, diorite, microgranite and sediments and another ceramic sherds, soils, marble schists, breccia. Such linear regressions become readily available for a future fast, efficient and accurate way of potassium determination.