Copper mining in the United States the northwest part of the state in the early 1850s, and mining began in 1855. The ore is massive sulfide and disseminated ore in mica schist and gneiss, and amphibole schist and gneiss. The principal ore mineral is chalcopyrite, which occurs with pyrrhotite and pyrite, The mine operated until 1883, then worked sporadically until large-scale mining began in 1957. The mine closed for good in 1962. Total production was 31,000 tonnes of copper, 9,400 ounces of gold, and 145,000 ounces of silver. Copper was mined at Creta from 1965 to about 1975. The ore 2% to 4.5% copper as chalcocite
Ore algebra commutation in the definition makes Ore algebras have a non-commutative generalization theory of Gröbner basis for their left ideals. 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