A cut and paste, so not too specific, but gives some idea. Hope it helps
Metals are often found as compounds in ores. An ore is a rock or mineral that has enough metal in it to make it worth extracting. In the case of copper, it is worth extracting when there is about 2 kg of copper per 1000 kg of ore.
The main ores of copper are:
chalcopyrite
bornite
malachite.
The ores are extracted by either traditional mining (open pit or underground) or by leaching. The copper is then recovered using physical and chemical techniques.
Copper mines are only set up where there is more than 5kg of copper per tonne of rock (0.5% by mass). Ideally, the figure should be closer to 2%.
Copper can be extracted from its ore by sinking a vertical shaft into the Earth to an appropriate depth and driving horizontal tunnels into the ore.
However, most ore is mined by open pit method. Ores near the surface can be quarried after removal of the surface layers.
Leaching the ore, is done by treating it with dilute sulphuric acid. This trickles slowly through the ore dissolving copper to form copper sulphate. The copper is recovered by electrolytic refining. Advantages of this process are:
• much less energy is use than in traditional mining
• no waste gases are given off
• it can be used on ores with as little as 0.1% copper - for this reason, leaching extraction is growing in importance.
About 80% of all copper extracted comes from sulphide ores.
A typical ore contains only 0.5% to 2.0% copper. It is a measure of the value of copper that it is worth extracting it from such small concentrations. The ore is a mixture of minerals and rock (called gangue).
Concentrating the ore.
The ore is crushed, ground and then enriched (concentrated) by Froth Flotation.
The powdered ore is mixed with a special paraffin oil which makes the copper mineral particles water repellent. It is then fed into a bath of water containing a foaming agent which produces a kind of bubble bath.
When jets of air are forced up through the bath, the water repellent copper mineral particles are picked up by the bubbles of foam. They float to the surface making a froth. The unwanted waste rock (gangue) falls to the bottom and is removed.
The froth is skimmed off the surface and the enriched ore (mainly the copper mineral) is taken away for roasting. The mixture of water, foaming agent and paraffin is recycled.
After this stage the enriched ore now contains about 25% copper by mass.
At this stage of the process, the chemical reactions begin. They convert the copper minerals into copper metal.
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