 So we'll just go through a bit more detail of how we can refine other metals other than active metals. So copper is a good example of a metal that's refined using an electrolytic cell. So they make some impure copper first from the copper ore. So that's impure copper. It's normally about 95% pure. So there's other impurities, there's slag, there might be gold and there might be silver in there too. So by refining it this way you can collect some valuable metals. So the anodes, and at the anodes the copper gets oxidized and both of the electrodes are placed in a copper sulfate solution. So as the copper is oxidized you get more copper ions in the solution and then over the other side you get the copper being reduced. So the copper ions from the solution are reduced to pure copper metal and they're usually plated on pure copper cathode. And that is what can be sold. So you sell the copper cathodes because they have 99.999% pure copper. So here's a picture of what would happen. So here you have your impure copper blister copper anode. So it's not very pure. That's being oxidized to copper ions in the solution. And when that happens any less reactive metals like silver and gold they form a little pile underneath here. That's called anode mud and that can be quite valuable to recover. The copper ions go into solution and then they are reduced over at the cathode. The copper ions are reduced to pure copper. So here we can see a very old photo. We can see some of these sheets. So this is pure copper here. So these are pure copper cathodes that are dangling in the solution. And that's like I said, you take those out, you cut off the ends and then that's what you sell.