Characterization of Tailings of the Rammelsberg Ore Deposit for a Potential Reprocessing

Dr. rer. nat. Thomas Schirmer, M.Sc. Felix Römer, Prof. Dr.-Ing. Tobias Elwert, Prof. Dr.-Ing. Daniel Goldmann

Against the background of increasing resource demand driven by a strong population growth and fast developing societies, mining activities have had to resort to lower quality ore deposits over the last decades with sometimes severe environmental impacts.

Although process efficiencies have been improved, a notable share of the valuable minerals is lost during mineral processing either as tailings or dump material. In future, these anthropogenic ore deposits may get more attention due to both environmental and economic reasons. Especially older deposits may contain higher ore concentrations because of less efficient mineral processing technologies. Furthermore, the extraction of some metals, i.e. minor metals used for modern information and communication technology, was no primary goal.

In this regard, the mining residues might even contribute to the global resource supply for these metals. For this reason, a German research project was initiated to exemplarily investigate and characterize the tailings of a closed German mining site at the Rammelsberg synsedimentary-exhalative ore deposit, aiming at the development of an effective reprocessing route. This paper presents a first mineralogical characterization of the tailings to clarify the presence and incorporation of valuable metals like Cu, Zn, Pb, Ba and to a lesser extent Co, Ga, Ag and In. Furthermore the implications for mineral processing are discussed.