Countermark

Similarly, foreign coins could be marked as legal or accepted currency, thus allowing them to circulate in the area where they were countermarked.

Some experts recommend not to use the term countermark and counterstamp as synonyms, but in different contexts.

Often countermarks are applied by private persons, as is the case with chops (often referred to as chopmarks), which were punched by money changers, bankers or shroffs onto foreign coins circulating in China in the 19th century.

An example of this would be post WWI in now modern day Germany to show hyperinflation.

The term punchmark is mainly used when referring to the earliest Indian silver coins which are coin-like pieces of metal of a standard weight that are bearing various symbols which were applied with punches, resulting in what are known as punchmarked coins.