Report Toned Coins in Coin Forum Posted May 20, 2009 This might sound a bit of a silly question, but what is the main cause of toning? Is it just use and contacts with chemicals etc, or is it something more unique to certain metals and compounds?
Toned Coins
in Coin Forum
Posted
This might sound a bit of a silly question, but what is the main cause of toning? Is it just use and contacts with chemicals etc, or is it something more unique to certain metals and compounds?