They are smashed into a dust, which is frothed up in a special liquid solution that helps separate the copper from the rest. After that some of the dust is smelted and electrolysed, emerging as nearly entirely pure slabs of glistening copper – cathodes as they’re called. The rest – ‘copper concentrate’, a kind of dark, granulated earth which has about 30 per cent copper – is sent elsewhere to be refined into the finished article.
