Do you see any writing on it? This is the only one I found in my book that looks similar.
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I wouldn't do this. I broke a Roman Silver Coin, Pewter is way to risky, it may have faults you can't see. Soapy water & a tooth brush is fine, you just need to make sure it drys out well before you seal it.Get a set of the Andre's Pencils. Go slowly. Don't use water. Toothpicks also work but take forever. You slowly scrape the dirt away from the numbers, and there are letters on the top and bottom. Go sllloowwww.
I think you may have nailed it cannon ball and grasshopper. Here is a better pic is there anything I can do to clean it? I am good with old coppers but not pewter
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