Chapter 6 Copper Production Technology ... As early as 6000 B. C., native copper–the pure metal—was foundas reddish stones in the Med
Jets of air are shot up through the water forming bubbles that float the water repellent copper particles to the surface. The froth, which contains about 30 percent copper, 27 percent iron and 33 percent sulfur, is skimmed off and taken for roasting.
Gold and Copper Processing Methods . Gold is extracted from naturallyoxidized ores by either heap leaching or milling, depending on the amount of gold contained in the ore, the amenability of the ore to treatment and related capital and operating costs.
Leaching and recovery of platinum group metals from UG2 ... sulphides to oxide phases and native ... work was carried out on a copper/nickel float
The native copper extraction apparently showed the same behavior, with little increase in the results, confirming the small variation in final percentage of extraction in relation to time. Therefore, the sulfuric acid leach residue was % copper, of which % was undissolved native copper.