Any time a chemical comes into contact - in particularly with a copper coin surface its some form of cleaning. All three cleaners (Verdi-Care, Xylol & JPL Coin Care) have one thing in common a nuetral pH. Indeed solvents like isopropyl alcohol, keteon, actone, methyl ethyl ketone are nuetral solvents but other than xylol most can turn a surface whitish through dry out. Decontamination is just another word for soil removal. I agree acetone is cheap and plentiful but if necessary its best to use one of these materials IMO. I have heard of complaints of the high shipping of Verdi-Care to the U.K. and I sell my product only to fellow collectors who are either desperate or who I have known for awhile. I use chemicals no longer available on the open consumer product. But we can argue in circles. Anyone who wishes to try it I can send them a bottle. There was another topic in terms of toning. The two main contaminants in the open air which tone coins are chlorides and sulfur. A book William Weimer on Coin Chemistry does this subject very well and this is confimed on some BNJ and RNS metalluricial studies from guys like Craddock and Northover. One trick I used is taking sulfur gel which is used by Afro-Americans as a hair product. It contains a large amount of sulfur - apply a small dab inside a paper envelope and let the coin sit in there for a year. There was some comments that a cleaned coin may never properly retone. Its false. Its works pretty well and to achieve rainbow toning stick a silver coin wrapped in aluminum foil in a toaster oven for 400*F for 30 minute intervals. Try it. Understood - you can't remove surface hailrlines if its part of the cleaning process - obviously. Carbon spots can't be removed from copper proofs and copper spots on gold coins need to be left alone. last night I spoke to the largest group of metal detectors in the East Coast of the U.S. - ironically - but it was interesting. yes - I did recommend these (3) products. Yep - acetone came up again. I would use it only to remove that sticky surface from a copper with a QUICK q-tip application. Agree ... just to be clear ... other than ground burial why would anyone decontaminate a silver or gold coin? John Lorenzo Numismatist United States johnmenc@optonline.net