a cleaned coin takes away from the value of a coin,dipped or other wise. If a coin looks to shiny and the details don t match its a safe bet its been cleaned.I personnaly won t buy a high grade coin unless its certified by 1 of the 3 major companys pcgs,ngc,anacs.. This makes it easier to sell down the road or to upgrade your collection. Some ef, vf,au grades are cleaned to make coin appear better to the buyer.Sometimes a little dirt is better than a lot of shine.Sometimes if you look around the lettering you can see a build-up of cleaner or abraisions from cleaning.Remember collecting is a hobby and an investment so take time to read feedbacks. GOOD LUCK HERE IS AN EXAMPLE ,BOUGHT THIS RAW AND SENT TO GET CERTIFIED.