Determination of copper in geological materials by X-ray fluorescence

X-ray fluorescence has been applied to the determination of copper content of geological materials in the concentration range of 0.01 to 2t=. CuO. A molybdenum target tube is used, samples being presented in finely-ground power form. Various methods for the correction for background and instrumental copper interferences have been considered. To correct for matrix effects different tube scattered primay radiations have been tested as references or internal standards. MoKβ1,3(C) provides the most suitable results. The use of influence empirical coefficients for the effect of iron on copper and of mass absorption coefficients has also been considered. For samples with a high content of lead, several procedures to correct for its influence have been investigated. Comparison between data obtained by X-ray fluorescence and wet-chemical techniques indicates good agreement.(auth.)