Copper was first mined in this area by an ancient vanished race between 5,000 and 1,200 bc. These miners left no burial grounds, dwellings, pottery, clay tablets or cave drawings. What was left behind was thousands of copper producing pits and more thousands of crude hammer crusher with which the pits had been worked. In the winter, travel was by dog sled. Boom towns sprang up everywhere around the mines. Boy Scouts of America: the source for more info. These mines produced most of the world s copper. Our company is a professional copper mining equipment producer and exporter. More than 20 years, we have established lots of copper mining crushing plant.
The copper mining equipment is mainly divided into two kinds that are copper crusher and grinding equipment copper. To provide more advanced copper mining equipment, there is mobile copper crusher plant invented by our engineers. Mobile crushing plant copper has been widely applied for Zambian copper mining. Shortly the fabulous Cliff pre-Renaissance Mine began producing the first mass that was not also float copper copper. The Cliff Mine was near Eagle Harbor, 19 miles west of Copper Harbor (Map). Huge pieces of metal, some weighing more than 50 tons, were discovered where they had been deposited. They lay deep beneath the surface, undisturbed by the glaciers which had gouged out so many other specimens, scattered them around the country and tricked so many early miners. In 1849, the Cliff rich vein rock hit.
Pure copper masses, some weighing 100 tons, were hammered, chiseled, cut in pieces and hauled to the surface, blasted bit by bit. When copper concentrates are processed by jaw crusher, the precious metals are generally recovered in high yield (about 90 98%). The extra cost to the copper smelter/refinery of such precious metal recovery is quite low. The precious metals follow the copper through the various steps of smelting and converting to blister copper matte; the blister copper is then usually refined by electrolysis to remove impurities and refining process precious metals report almost quantitatively to this during the (refinery) anode slime, which has a low mass (typically only a few kg per tonne of copper metal). The anode slime therefore has a high concentration of said relative to the original copper concentrate fed to the smelter metals, e.g. 1000X more concentrated. Such low mass and high concentrations of gold and silver in the slime lead to low processing costs for final recovery and refining.