Copper, as with virtually any mined metal, does not exist in nature in easy-to-remove forms. The copper ore mining and refining process is brutal, to say the least. And the methodologies used to mine and refine copper ore differ. Poorly refined copper contains impurities, or non-copper elements, much like 10K gold is inferior to 24K gold due to the presence of non-gold elements. The better, or more purely refined the copper ore, the higher pure copper results, and so does a higher price. Poorly refined copper can be had for cheap, but it is not pure copper.