Chalcopyrite ore types, from huge masses as at Timmins, Ontario, to irregular veins and disseminations associated with granitic to dioritic intrusives as in the porphyry copper deposits of Broken Hill, the American cordillera and the Andes. The largest deposit of nearly pure chalcopyrite ever discovered in Canada was at the southern end of the Temagami Greenstone Belt where Copperfields Mine extracted the high-grade copper. Chalcopyrite is present in the supergiant Olympic Dam Cu-Au-U deposit in South Australia. Chalcopyrite may also be found in coal seams associated with pyrite nodules, and as disseminations in carbonate sedimentary rocks. Crystallographically the structure of chalcopyrite
Iron ore in the table aside. The major constraint to economics for iron ore deposits is not necessarily the grade or size of the deposits, because it is not particularly hard to geologically prove enough tonnage of the rocks exist. The main constraint is the position of the iron ore relative to market, the cost of rail infrastructure to get it to market and the energy cost required to do so. Mining iron ore is a high volume low margin business, as the value of iron is significantly lower than base metals. It is highly capital intensive, and requires significant investment in