mineral resources are: 1,170 mt of ore with 4.2 mt of contained copper at an average grade of 0.36%. aktogay is the group's second largest project, located in eastern kazakhstan. mineral resources are: 1,597 mt of sulphide ore at 0.33% copper grade and 121 mt of oxide ore at 0.37% copper grade.
a group of mines on ecton hill, staffordshire, are unusual for the peak district in producing predominantly copper rather than lead and zinc. the most important, deep ecton mine, has been mined since the bronze age, and in the 18th century was a major producer of copper, and the deepest mine in britain.
copper mining in arizona, a state of the united states, has been a major industry since the 19th century. in 2007 arizona was the leading copper -producing state in the us, producing 750 thousand metric tons of copper, worth a record $5.54 billion. arizona's copper production was 60% of the total for the united states.
although native copper was the dominant ore mineral, chalcocite copper sulfide was sometimes present, and, especially in the mohawk mine, copper arsenide minerals such as mohawkite and domeykite. gangue minerals included calcite, quartz, epidote, chlorite, and various zeolites.
the mineral cattierite is similar to pyrite and occurs together with vaesite in the copper deposits of katanga province. when it reaches the atmosphere, weathering occurs; the sulfide minerals oxidize and form pink erythrite 'cobalt glance': co 3 aso 4 2 ·8h 2 o and spherocobaltite coco 3 . cobalt is also a constituent of tobacco smoke.
the south caradon copper mine, 1 km to the southwest of the caradon hill transmitting station, was the largest copper mine in the uk in its heyday in the second half of the 19th century. other disused copper and tin mines are scattered around the base of the hill.
mining of non-ferrous minerals, particularly of copper and tin, has been ongoing since the bronze age. for example, copper was mined in wales during approximately 2200–850 bc. 4 metalworking debris found beneath the ramparts at beeston castle in cheshire is evidence of bronze production during the bronze age.