Practicing hoodoo style magic, I don't have a frequent need for cauldrons; but from time to time, a small paper needs burning or a few herbs need to be scorched, and in that case a cauldron comes in handy.
I bought this thing a few years ago for $2, second hand. Not the prettiest thing on earth but it was functional. This photo shows it being used in a recent ritual.
It looks old, worn, scratched and blackened from years of use. The spots on it were permanent -- no dish soap I ever used got them off, and they seemed to just be the result of metal tarnish.
After the ritual above, I decided to give the cauldron a special cleaning with some copper cleaner, simply thinking it would brighten it up a little and not at all expecting what occurred....
For those who are curious, this was the cleaner responsible for the miracle. Seriously, though -- "Make old copper look new" is the kind of thing that would have been classed as magic at one point in time.