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
Ore algebra Ore algebra In computer algebra, an Ore algebra is a special kind of iterated Ore extension that can be used to represent linear functional operators, including linear differential and/or recurrence operators. The concept is named after Øystein Ore. Let formula_1 be a (commutative) field and formula_2 be a commutative polynomial ring (with formula_3 when formula_4). The iterated skew polynomial ring formula_5 is called an Ore algebra when the formula_6 and formula_7 commute for formula_8, and satisfy formula_9, formula_10 for formula_11. Ore algebras satisfy the Ore condition, and thus can be embedded in a (skew) field of fractions. The constraint of