The gold contents obtained with this method are
approximately five weight percent higher than those
determined by GD-OES. This could be explained by the
gold rich surface detected with the latter method and the
fact that EDX is still a surface analysis. Further, the
preform used for calibration could show the tin
segregation described in the literature. This would
introduce an error into the calibration so that the gold
contents of the samples are determined to a higher value
than realistic. The lateral distribution of the elements
shows a fine and homogeneous texture. By variation of
the acceleration voltage a very slight increase of the gold
content could be interpreted.