Jonathan V. writes:Â Hi. I have begun to collect Byzantine coins, and have two questions. First, I realize that one never cleans modern coins, but what about ancient coins? Some of the coins I have come across are dirt-encrusted; one dealer suggested using a toothbrush, “but nothing chemical or abrasive.” Would that include water to loosen the dirt? Second, is there any price guide more recent than the Sear guide from 1987? Many thanks for your help!
There is an art to caring for ancient coins. The metal can crystallize over long periods of time and the coin can shatter like glass if hit hard enough. Copper coins are especially vunerable to damage from metal “diseases”. Soft brushes can be beneficial to copper coins such as sestertii, dupondi and asses. An occasional soak in olive oil to lubricate the metal is often done also. Unfortunately, there are few ancient coins that haven’t been cleaned at one time or another. Our aim is to preserve what we have remaining for posterity.
If you are interested, seek out professional numismatists who specialize in these coins to gain some knowledge about the techniques for preserving ancient coins. You might want to subscribe to some of the auction houses that specialize in ancient coin sales. That is the best source of current pricing.
