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.
Ore Mountains one overarching unit, the Saxon Highlands and Uplands. In addition, its internal divisions were changed. Former major unit 420 was grouped with the western part of major units 421 and 423 to form a new major unit, the Western Ore Mountains ("Westerzgebirge"), the eastern part of major units 421 and 423 became the Central Ore Mountains ("Mittelerzgebirge") and major units 422 and 424 became the Eastern Ore Mountains ("Osterzgebirge"). The current division therefore looks as follows: The geographic unit of the Southern Slopes of the Ore Mountains remains unchanged under the title of Southern Ore Mountains ("Süderzgebirge"). The climate of