ANALYSIS OF RARE-EARTH ELEMENTS IN ROCK SAMPLES BY INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY (ICP-MS)

An ICP-MS method for quantitative analysis of ultratrace elements of r are earths in minerals has been developed. Samples are analyzed direct ly following an acid digestion, without the need for separation or pre concentration, with limits of detection, precision, and accuracy bette r than that seen with inductively coupled plasma emission spectrometry and instrumental neutron activation analysis. Examples are reported o f ICP-MS semiquantitative and quantitative analysis of rock samples. R esults show that ICP-mass spectrometry provides enormous potential for rare earths analysis, because of its increased capability in discrimi nating among elemental species. (C) 1995 Academic Press, Inc.