processing of blister copper from smelting concentrates or scrap which is not direct melted. The reason is on the one side that only very pure copper has a high electrical conductivity and on the other hand it contains also some precious metals which can be recovered. Normally copper is always electrorefined, but in some cases it is fire refined if it does not contain precious metals and the quality is enough for certain semis.
see also blister copper; copper anode
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