I get a lot if silver plated contacts from electric ranges and washing machines and the like, one time I stood my bench grinder on a peice of 2 x 6 planking to keep it dry. This sat in a water proof wooden box that I had made, then added an inch of water for a pump used an old aquariium air pump to circulate the water over the grinder wheel..
The aquarium pump is a diaphram pump which will handle air or liguids, anyhow in my spare time I owuld sit and listen to tunes and grind off the silver which would collect in the box below the grinder. This works great for those plated contacts and those too small for a torch.
When I had the hammer mill I would feed it whole circiut breakers the silver would settle to the bottom of the bucket with a bit of coaxing, shaking the bucket.
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