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.
Hajigak mining concession minor chalcopyrite. The remaining 20% is oxidized and consists of three hematitic ore types. The deposit remained unmined in 2006. The presence of coking coal nearby at Shabashak in the Dar-l-Suf District and large iron ore resources made the deposit viable for future development of an Afghan steel industry. Open pit mining and blast furnace smelting operations were envisioned by an early feasibility study. The Hajigak also includes the unusual niobium, a soft metal used in the production of superconducting steel. History reveals that Germans were the first one to exploit this deposit systematically after planning a steel mill during