Extraction and purification of copper. Copper is less reactive than carbon, so it can be extracted from its ores by heating it with carbon. For example, copper is formed if copper oxide is heated strongly with charcoal - which is mostly carbon:
Extracting of Copper from Other Ores. Copper can be extracted from non-sulfide ores by a different process involving three separate stages: Reaction of the ore (over quite a long time and on a huge scale) with a dilute acid such as dilute sulfuric acid to produce a very dilute copper(II) sulfate solution.
The process. The concentrated ore is heated strongly with silicon dioxide (silica) and air or oxygen in a furnace or series of furnaces. The copper(II) ions in the chalcopyrite are reduced to copper(I) sulphide (which is reduced further to copper metal in the final stage).