ABSTRACTIn the framework of the natural analogue Matrix Project, performed in the U-ore deposit of Mina Fe(Salamanca, Spain), the determination of the mineralogical distribution of some analogue elements (U, Ra, Co, Ni, Se and REE) in fracture fillings has been relevant to establish their sources and sinks. In order to fulfil this objective, selection of a suitable sequential leaching method was necessary. For this purpose, a comprehensive review of the selective and most relevant sequential leaching procedures published in the literature has been firstly done. Second, the efficiency of the most critical reagents on some pure minerals, as well as the cross contamination observed, has been considered; and third, the results from the application of three selected procedures on a representative sample of the site, previously characterised from a mineralogical and chemical point of view, are presented and discussed. One the main conclusions of this work point to the difficulty of setting a universal sequential leaching method for any geological sample. Nevertheless, a suitable and approximate procedure for Fe (III)-U (VI)- rich samples is proposed.
Buy this Article
|