Geological sources rare earth elements

Determination of rare earth elements in geological samples by ICP source mass spectrometry, J Anal At Spectrom 2 269-281. 

Barba and his colleagues sampled the three outcrops of limestone to determine their distinctive signatures. This information was compared to lumps of calcium carbonate found in the finished plaster in the city. The group of scientists used several different techniques to examine the samples. The major element composition of the geological samples was determined by XRF. The major element composition of the lumps was determined by SEM-EDS. Trace element composition was determined by LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry) to measure the elemental composition of the plaster and the limestone. This methodology is well suited for analyses of very small lumps with microscopic spot sizes. The LA-ICP-MS method is able to analyze a large number of trace and rare earth elements with speed, precision, and high resolution, especially in cases where the major chemical composition does not appear to be particularly distinctive. The instrument worked extremely well for the characterization and determination of the provenance of the Ume plaster source material. 

Date, A. R. and Gray, A. L. (1983) Progress in plasma source mass spectrometry. Determination of rare earth elements in geological samples by inductively coupled plasma source mass spectrometry. Spectrochim. Acta Part B At. Spectrosc., 38(1-2), 29-37. 

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