Acid mine drainage where the ore is a sulfide mineral or is associated with pyrite. In these cases the predominant metal ion may not be iron but rather zinc, copper, or nickel. The most commonly mined ore of copper, chalcopyrite, is itself a copper-iron-sulfide and occurs with a range of other sulfides. Thus, copper mines are often major culprits of acid mine drainage. At some mines, acidic drainage is detected within 2–5 years after mining begins, whereas at other mines, it is not detected for several decades. In addition, acidic drainage may be generated for decades or centuries after it is first detected.
Central Ore Mountains Central Ore Mountains The Central or Middle Ore Mountains ( or "Mittelerzgebirge") is a natural region that forms the central-western part of the Ore Mountains in the German federal state of Saxony. It is part of the overarching unit, the Saxon Highlands and Uplands. It forms the eastern part of the former major units, the Lower Western Ore Mountains ("Unteres Westerzgebirge", 423) and Upper Western Ore Mountains ("Oberes Westerzgebirge", 421) and is separated from the Eastern Ore Mountains in the east by the (included) valley of the Flöha, and from the Western Ore Mountains in the west by the (excluded)