Beneficiation of the Nechalacho rare earth deposit. Part 2: Characterisation of products from gravity and magnetic separation

This work employs automated mineralogy (QEMSCAN), scanning electron microscopy and a vibrating sample magnetometer to characterise the products from laboratory gravity separation (Knelson and Falcon centrifugal concentrators) and magnetic separation (varying intensity wet drum magnetic separators). The information gathered is then used to identify the optimum fraction for downstream flotation separation. The selected flowsheet included a Knelson centrifugal concentrator and low intensity drum magnetic separation resulting in a total rare earth oxide (TREO) recovery of 11.75% and a TREO grade of 7.50%.