Properly Cleaned? So We See The Improperly Labels Often!

Thanks! So any tips for a newbie on what to do and not do with EZest? I read that you dip the coin for a few seconds. Should you do something else instead? Apply it only to the toned area? Looking for advice so I don't ruin any silver coins! Is the danger to dip them too long?

I got the ultrasonic machine and tried it on some "melt silver" that I eventually plan on selling as melt when silver gets to a certain price. It didn't do anything - good or bad - that I could tell. I did numerous "cycles" with distilled water and then a little dish soap and didn't see anything come off at all. So I am giving up on that supposed method. Since some say it could harm anyway! Will use it for other things only instead.