Rare Earth Elements (REEs) Measurement in Coal and Rock Mineral Matrices

Two REEs, La and Nd were studied in two different mineral matrices, coal-based and rock-based simulants representing natural major REE deposits.In addition, six test samples obtained from the natural sites were also tested to evaluate the presence of La and Nd.Emission signals were detected in some of the samples to confirm their presence.Principal component analysis (PCA) was performed for clustering to evaluate if the samples were significantly different from each other and the clustering demonstrated that two simulants and the test samples were significantly different from each other.Miniaturized LIBS probe was also used for the measurements and results are promising to show that LIBS technology can be useful for in-situ filed measurements to detect and evaluate REEs in natural deposits.For the La and Nd emission lines considered, signal enhancement of 3.5 to 6-fold compared to single pulse was observed with double pulse LIBS.