I use a tumbler and gravel which is similar to aquarium gravel. I do not use dish detergent since it is harder to rinse out than a cap full of mister clean. I now take my tumbled clad to many vending machines and turn them into clean coins that I can then roll and deposit into my bank account without any hassle. I used the coin-star once and it rejected many coins that some vending machines would take. No more coinstar for me. Just think I might come across some silver coins out of the vending machines. Just today I exchanges $25 in quarters and $15 in dimes using 3 vending machines at the local Walmart. Once the vending machine begins to give me my discolored clad back, I move to the next one and continue.
You have a lot of free time on your hands, lol.
Good idea if you don't have a choice. I have a 3 lb coffee can full of clad and counting. It would take a lot of vending machines to convert his much.
I do the gravel and dish soap method in my tumbler. Takes about 45 minutes for about a pound of clad. I bet you could use borax detergent also. I use borax to tumble rocks along with the grit. Keeps the foaming down.