How to clean copper cobs?

[13blindeyes]

I recently came into a small batch of uncleaned(landfound) copper cobs and I am wondering the best way to clean them up to add them to my collection.

much obliged in advance

 

[petersra]

I really don't think you want to clean them any more than necessary to get the dirt off and stabilize the coin so it does not continue to corrode. As with most old copper coins, the patina adds value to the historic authenticity of the coin. Clean it too much and you take away a large amount of the historic value of the coin. I am not an expert, just my opinion. Good Luck. Ralph