Abstract
The zinc content of soil samples that contained different amounts of organic matter was determined by X-ray fluorescence spectrometry with a modified background-ratio method. The ratio, IZn Kα/I1·17 B, in which IB is the background intensity at 39·50 °2θ, was substantially independent of matrix for the range of zinc contents investigated. The results correlated well with those obtained by atomic-absorption spectrometry.