Depending on the country, there are several classification systems to describe the condition of the coins, the most complex being certification bodies found in the United States.
In order to have a simpler and more universal system, we classify the condition of the coins in 4 levels:
Perfect : the coin is of perfect quality, as if it has just been manufactured. It must be free of marks or scratches.
Good : the coin has slight scratches or marks that do not harm its general aesthetics.
Medium : the coin has serious scratches or major discolorations, harming its the general aesthetics.
Poor : the coin is damaged to the point it has lost much of its aesthetic qualities.