This video shows just how easy it is to clean small or large silver pieces using aluminum foil, baking soda and very hot water. The hot water is crucial - warm water from the sink won't do the job - you must get the water boiling or close to boiling for this to work well.
One large sheet of aluminum foil and a few sprinkles of baking soda in very hot water, just make sure the container is big enough to submerge the pieces and that the piece is in contact with the foil.

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