Floatation characteristics of a cassiterite bearing complex skarn ore from the Ore Mountains, Germany

The flotation characteristics of a cassiterite bearing fine grained and complex skarn ore from the Ore Mountain region is investigated. A sulfosuccinamate type collector is used and sodium hexafluorosilicate is added as depressant. The objective of the experiments is a better understanding of the cassiterite flotation performance as influenced by different pre-processing operations as magnetic separation, gravity separation, sulphide flotation and desliming. Therefore, structure and composition of the feed, the different concentrates and the tailings of each process are analysed in detail by XRF and MLA to get a better understanding of the behaviour of the single ore components in the different processing steps. Problematic minerals (e.g. chlorites) have a negative effect on the selectivity of cassiterite flotation. Therefore, particular attention is payed to the behaviour of these minerals during flotation. Furthermore, the effect of the particle size due to the change in liberation on the flotation process is investigated. Three critical factors are found to greatly influence the flotation performance, namely: (1) particle size; (2) Fe oxides content; and (3) ions in the solution.