Myriam Ruttmann

PhD student

DFG Project in the framework of SPP “DOME” 2238

“Enrichment processes during transfer of chromium from the mantle to the crust”

Dynamics of Ore Metals Enrichment (
PIs: R. Botcharnikov, E. Moulas, S.Buhre

Chromium is a critical metal with a high importance to the economy of the EU and high rick of sustainable supply. Chromium has been mined from four different deposit types: stratiform, podiform, placer, and laterite deposits in the form of chromite mineral but only stratiform and podiform chromite deposits represent the most significant types. Only podiform Cr deposits, intimately associated with mafic-ultramafic rocks, are present and currently mined in the EU. The close association of Cr deposits with mantle rocks dictates that the source of chromium in the formation of chromite deposits must be sought in the Earth’s upper mantle. The very low concentrations of Cr needed to saturate magmas with chromite indicate that seemingly limited extraction processes both during mantle melting and during magma crystallization appear to be sufficient to generate podiform chromite deposits. However, despite numerous studies and a variety of proposed mechanisms leading to Cr enrichment, there is a lack of general consensus on a particular model which can fully explain the formation of podiform chromite deposits. In our research we aim at understanding the processes leading to the Cr enrichment in magmatic systems from the mantle to the ore deposit.