For those just beginning to collect Roman coins--or those who want to feel a little closer to those who found the coins in the ground--uncleaned coins are a fun way to begin a collection. Large commercial dealers often give instructions for cleaning coins safely; scrubbing off dirt with abrasives or even vigorous brushing can destroy minted details and valued patina. Reputable dealers offer uncleaned coins in lots from 10 to over 100 at prices well below those of cleaned coins. They also offer good-sense warnings. They are, after all, dealers and they've had an informed peek at the coins. You are unlikely to spot a valuable gold or silver coin they have missed. Your chances of fabulous wealth are therefore very low! For learning about coins, though, an uncleaned mystery-batch brings you very close to coin-collecting in a meaningful way. Clean by hand pieces of history that were made by hand, and enjoy what you find!