The Erzberg mine is a large open-pit mine located in Eisenerz, Styria, in the central-western part of Austria, 60 km north-west of Graz and 260 km south-west of the capital, Vienna. The deposit lies at the Northern fringes of the Eastern greywacke zone, a band of Paleozoic metamorphosed sedimentary rocks that run east-west through the Austrian Alps, rich in copper and iron ore. Erzberg is the largest iron ore reserves in Austria, having estimated reserves of 235 million tonnes of ore. The mine produces around 3.2 million tonnes of pure iron ore per year.