Concentration of copper ions in refining of copper metal during electrolysis

When refining copper, would there be a circumstance when the concentration of copper ions in the electrolyte drop? I only know that when refining copper the color of the solution should remain the same blue color.




If the copper to be refined is an alloy of copper plus some less electronegative metals, like zinc, both metals are oxidized and dissolved at the anode. But only copper is reduced at the cathode. So the solution contains more and more zinc. As a consequence, it contains less and less copper. And the solution becomes less and less blue.


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