Critical comparison of sample preparation methods for major and trace element determinations using X‐ray fluorescence

Ten geochemical reference rocks were used to evaluate the preparation of glass disks and pressed powder samples and counting errors in XRF analyses. Disks prepared with and without heavy element doping at various dilutions with lithium tetraborate demonstrated that all of the methods were limited by preparation errors and that they would give comparable precisions for the 10 major and 12 trace elements determined. However, simplicity of preparation, precision of analysis and total analysis times favored 10:1 or 3:1 dilutions without doping over the doped or pressed powder methods.