The Erzberg Mine is situated in the Austrian county of Styria. From a geological point of view, it belongs to the so-called greywacke zone, which represents a band of Palaeozoic metamorphosed sedimentary rocks intercalated between the Northern Limestone Alps and the Central Alps. The Erzberg Mine is the world’s largest deposit of the iron mineral siderite (FeCO3), which is mixed with ankerite (CaFe[CO3]2) and dolomite (CaMg[CO3]2). Due to this mixture of different mineral phases, the concentration of iron ranges from 22% to 40% and adopts an average value of 33%. The annual output amounts to about two million tons of iron ore, which is transported to blast furnaces in Linz and Leoben-Donawitz. According to current estimations, the ore reserves will allow mining activity for another 30 to 40 years.
History of the Erzberg Mine
There are lots of myths regarding the founding date of the iron mine on the Erzberg. According to the opinion of several scholars and a few written documents of dubious veracity, the mine was already established in the year 712, which would imply a use of the deposit by Slavic peoples. However, there exists better evidence that foundation of the mine took place in 1512, which was also the inauguration year of the Oswald church in the village Eisenerz.