Today I tried a new method (at least for me). I went to the dentist and tried to clean with the scaling device (ultrasound and water). I tested on 2 rust stains on a silver coin. I was amazed at the effectiveness. Has anyone tried it yet? Is that an ok method?
all I know is that this has a bad effect on copper or copper alloy coins with patina because it ruins the patina of the coin which holds detail on other coins however I have no idea.
Ultrasound works very well in my experience for just plain dirty coins (even those so dirty they could not be identified until cleaned) and does not ruin any patina. I have used it to remove tar and tape residue from coins. The tar completely covered one side but ultrasound removed about half and continued use would have removed more, in my opinion. I just use a cheap ultrasound cleaner recommended for use for jewellery but also for eyeglasses and DVDs.
