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7466196 
Journal Article 
The application of process mineralogy on a tailings sample from a beach placer deposit containing rare earth elements 
Moila, A; Chetty, D; Ndlovu, S 
2017 
SOUTHERN AFRICAN INST MINING METALLURGY 
MARSHALLTOWN L 
117 
7 
615-621 
English 
WOS:000412487700004 
The rare earth elements (REE) are significant in the context of world economic growth and modern technology. This research is aimed at investigating an alternative source of REE by exploring cost-effective ways of processing REE minerals from an existing beach placer deposit operation, currently mined for titanium. In order to recover REE through economically optimum means, upfront mineralogical investigations are a necessity to reduce the ore processing costs. An approach involving mineralogical characterization and hydrometallurgical test work was therefore chosen. The sample for the study - a tailings fraction from a heavy mineral concentration plant in the titanium industry - was screened into four size classes, and each size class was mineralogically characterized. The minerals present in the sample were monazite, zircon, epidote, pyroxene, amphibole, rutile, quartz, leucoxene, titanite, and almandine. The main REE-bearing minerals, monazite and zircon, were preferentially concentrated in the finer (-150 mu m) fractions, which constituted about 50 mass % of the sample and which would be amenable to direct leaching without prior upgrading to a concentrate. Leaching test work was carried out on the combined fractions passing 150 m. Mineralogical examination of the residues from different leach stages showed that monazite was cracked and the REE released to solution in the final leach stage. Zircon was not as reactive under the conditions used, and REE release was not expected from this mineral. The mineralogical findings were correlated against bulk chemical analyses of the leach products to establish whether a good reconciliation was achieved. 
rare earth elements; beach placer deposit; process mineralogy; leaching