A COMBINED CLASSICAL ION-EXCHANGE AND HPIC PROCEDURE FOR THE SEPARATION OF ND AND SM FOR ISOTOPIC ANALYSIS OF GEOLOGICAL SAMPLES

Abstract

Classical ion-exchange chromatography combined with high-performance ion chromatography has been used for the separation of Nd and Sm for isotopic analysis of geological samples by mass spectrometry. The procedure has successfully been applied to samples with Nd concentrations as low as 0.2 μg g-1 and high-quality elemental separation was routinely achieved even for ''difficult'' samples such as low-Nd ultramafic upper-mantle xenoliths and extremely Ba-rich lamproites. The total blank value was <60 pg Nd. The method has several distinct advantages: (1) it is simpler than some of the other techniques available; (2) it can be used for samples with low Nd and Sm concentrations; and (3) Nd and Sm fractions virtually free of interferences from other elements were obtained for a wide range of samples investigated.