Why tempt fate when there are non-invasive ways of achieving the same thing? Years of observation of the effects of similar chemicals' effects on stones apparently have no sway? Just a shaving cream specific test will suffice? When the faces of the stones are finally flat (as have been many I have seen in cemeteries) there is no going back. The information is lost forever. Seems like for you the easy way works, regardless of the ultimate, even if it is just remotely possible, effect it may have. Is that correct? Get in and get out? I'm not trying to be nasty but, again, why add something foreign to the stone when it is not necessary? All it takes is a "little" extra effort. Brec Morton Brock Way wrote: I hope in the meanwhile people and websites can refrain from suggesting that these studies have already been done, and that the results are in. Brock Way