Copper is refined electrolytically in a bath of acidulated copper sulphate solution by deposition on a cathode and is easily produced 99.96 to 99.99% pure. American copper contains about 110oz of silver and 1/2oz of gold per ton, which are collected as 'anode slime' with other metals. Other impurities dissolve as sulphates in the electrolyte.
Anode, 'poled' touch-pitch copper, before electrolysis, contains between 0.02% and 0.04% oxygen. This small amount is necessary to strike a balance with cuprous oxide, Cu2O , which renders the melt brittle but is part of the refining process to remove iron as a slag. Electrolysis may reduce oxygen levels further, but the common commercially produced metal, as drawn into wire, is essentially very pure indeed and virtually oxygen free. Yep, it's snake oil.
