Wolframite- and scheelite-bearing carbonate rocks of the Nock mountains,Austria: A new type of tungsten mineralization in the Eastern Alps

A new type of tungsten deposit was discovered in the Eastern Alps at the Mallnock, Nock mountains, Austria. The mineralization is restricted to concordant layers of carbonate rocks within phyllites belonging to the metamorphic Palaeozoic of the Upper Austroalpine Gurktal nappe system. Wolframite (ferberite 95) and scheelite occur as network fissure fillings in coarse-grained Fe-magnesite (siderite 15) rocks (average W content ca. 0.9 wt%); fine-grained dolomite marbles contain scheelite as the only tungsten mineral (average W content ca. 0.5 wt%). Assuming the dolomite marbles as a primary metal source, mobilization processes are responsible for the formation of the wolframite- and scheelite-bearing Fe-magnesite rocks.