Composite elemental standards for quantitative electron microscope microprobe analysis

In quantitative electron microscope microprobe analysis using the 'ratio method', standards containing known relative amounts of two or more of the sought elements are required. Techniques are described for the preparation of such standards using suitable oxides, hydroxides or silicate minerals. The method has been verified for five series of standards containing Si plus one of Mg, Al, Ti, Fe and K. Plots of characteristic X-ray intensity ratio against atom ratio were linear with coefficients of variation in the slopes between 1.7 and 5.0%. An example shows the application of the method to the analysis of kaolinite particles.