V-rich Minerals in Contact-metamorphosed Silurian Sedex Deposits in the Poblet Area, Southwestern Catalonia, Spain

The Lower Llandoverian metasedimentary rocks of the Prades Mountains, southwestern Catalonia, Spain, consist of interstratified anorthite-rich beds, chert beds, phosphate beds, sulfide-rich black shale (with mainly pyrrhotite and minor chalcopyrite), massive sulfide lenses and calc-silicate beds. These metasedimentary rocks are anomalously enriched in V and Cr, and have disseminated minerals of precious metals: mainly sperrylite and palladian löllingite. The Vand Cr-rich associations are the result of an isochemical metamorphism of Vand Cr-rich protoliths. The contact metamorphism of V-rich shale produced metapelitic hornfels with V-rich aluminosilicates and V–Cr oxides. The occurrence of V oxides in apparent equilibrium with Vrich silicates suggests a limit for the V and Cr contents in these aluminosilicates at the conditions of thermal metamorphism. On the other hand, metamorphism of anorthiteand V-,Cr-rich sedimentary rocks produced Vand Cr-rich silicates, such as goldmanite, V-rich amphiboles, V-rich titanite and V-rich allanite.