A procedure for the wavelength-dispersive x-ray fluorescence
determination of major, minor and trace elements in fused discs of base
metal sulphide ores and of iron-manganese oxide ores is described. The
objective was to obtain reasonable chemical analyses of ore samples of a
wide compositional range. Owing to the scarcity of well characterized
geochemical reference ore samples, calibration was done with synthetic
glass disc standards. The concentration range and the association of
the elements considered in the standards take into account the
geochemistry of most ore types. A fusion method with a high dilution
ratio (sample-to-lithium tetraborate ratio = 1:10) was used to reduce
the matrix effects. This allows a direct comparison of the synthetic
standards with unknown geological sample discs. Two different methods
of data reduction of the measured intensities were tested: (1)
intensity-based correction method for the determination of major, minor
and trace elements and (2) peak/background ratio method for the
determination of minor and trace elements. A critical evaluation of the
reproducibility, as judged from duplicate analyses, and the accuracy,
estimated by comparison with international reference materials, showed
the procedure to be capable of obtaining reasonable chemical analyses
for most elements of geological interest.