Fig. 1. Ratio, for two subsamples each of granodiorite JG-1a and granite JG-2, of concentrations of REEs (rare earth elements) in the subsamples to the mean concentrations for all subsamples analyzed. The deviation from unity considerably exceeds analytical uncertainty (12 %) and the magnitude varies systematically with atomic number (except for Eu, which is divalent). Subsampling error represented in this figure results from nonuniform distribution of REE-rich minerals such as allanite, apatite, monazite, xenotime, and zircon among the small subsamples. For clarity, data are not plotted for Nd because it is determined less precisely than the other REE.