Currency production

Group 11 elements (Copper group)

common and inexpensive metal

pattern of symbols incorporated into a number of banknote designs

security feature of banknotes

thumb|A silver coin of Charles IV of Spain, countermarked for local use by Chinese merchants in [[Sumatra (苏马德拉), also known as a chop mark]] A countermarked, or punchmarked or counterstamped coin, is a coin that has had some additional mark or symbol punched into it at some point after it was originally produced while in circulation. This practice is now obsolete.

intermediate used in minting coins

coin minting machine

numismatics collector's items