INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRIC DETERMINATION OF LOW-LEVEL RARE EARTH ELEMENTS IN ROCKS USING POTASSIUM-BASED FLUXES FOR SAMPLE DECOMPOSITION

The 14 naturally occurring rare earth elements, Sc and Y were determined in fusion solutions by inductively coupled plasma mass spectrometry with limits of quantitation similar to an acid digestion procedure. Two potassium-based fluxes (K2CO3 and K2B4O7) were studied as fusion media. To maintain the level of total dissolved solids within the range permitted by instrumental criteria, K and B were removed from the solution, thus avoiding the necessity for considerable dilution. The validity of the procedures has been verified by precision and accuracy tests on selected Standard Reference Materials.