Raman analysis of rock samples containing rare earth elements (REEs) is challenging due to the strong fluorescence, which may mask the weaker Raman signal. In this research, time‐gated (TG) Raman has been applied to the construction of the mineral distribution map from REE‐bearing rock. With TG Raman, material is excited with a short subnanosecond laser pulse, and the Raman signal is collected within a picosecond‐scale time window prior to the formation of a strong fluorescent signal by means of single‐photon avalanche diode array. This allows signal readout with a significantly reduced fluorescence background. TG Raman maps are used to reveal the location of valuable minerals and are compared with the elemental distribution given by laser‐induced breakdown spectroscopy. The analysis was carried out from a REE‐bearing rock, nepheline syenite sample from the Norra Kärr deposit, where REEs are mainly hosted in eudialyte and catapleiite. The combination of these two complimentary laser spectroscopic methods offers valuable elemental and mineralogical information about rocks.

Laser-induced breakdown spectroscopy (LIBS) has been used in analysis of rare earth element (REE) ores from the geological formation of Norra Kärr Alkaline Complex in southern Sweden. Yttrium has been detected in eudialyte (Na 15 Ca 6 (Fe,Mn) 3 Zr 3 Si(Si 25 O 73)(O,OH,H 2 O) 3 (OH,Cl) 2) and catapleiite (Ca/Na 2 ZrSi 3 O 9 •2H 2 O). Singular value decomposition (SVD) has been employed in classification of the minerals in the rock samples and maps representing the mineralogy in the sampled area have been constructed. Based on the SVD classification the percentage of the yttrium-bearing ore minerals can be calculated even in fine-grained rock samples.

Optimization of spodumene identification by statistical approach for laser-induced breakdown spectroscopy data of lithium pegmatite ores. Applied Spectroscopy Reviews, Early online.

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