The first mint marks on coins were called "Magistrate Marks" and were developed by the Greek to indicate the magistrate in charge of making that coin. Tampering with a coin was a crime often punishable by death. Many mints of the world now use a unique symbol called a mint trademark.

Coins from Canada: Since the end of 2006, the Royal Canadian Mint uses a symbol depicting a stylized maple leaf (for Canada) emerging from the the union of a crown and the letter M (for Mint and for “Monnaie” in French). The two components of the design evoke the action of two dies striking a coin.

Coins from France: Since January 1880, the symbol of a cornucopia has been used by the French Mint (Monnaie de Paris), and appears next to the General Engraver Master’s mark. Since July 2003, that second symbol is a French horn.

Coins from Poland: Since the end of the 19th century, a symbol made of the letter M over the letter W has been used as a trademark for the Warsaw Mint coins. It usually appears under the left foot of the Eagle, the state emblem of the Republic of Poland.

Coins from Russia: Russia uses symbols to differentiate production from the different mints: the St. Petersburg Mint and the Moscow Mint (pictured here).

Coins from Germany: Germany uses letters to differentiate production from the different mints: A for the Berlin Mint, D for the Munich Mint, F for the Karlsruhe Mint, G for the Stuttgart Mint, and J for the Hamburg Mint (pictured here).

Coins from the United States: The United States uses letters to differentiate production from the different branches of the United States Mint: P for the Philadelphia Mint, D for the Denver Mint, S for the San Francisco Mint, W for the West Point Mint, CC for the Carson City Mint, C for the Charlotte Mint, and O for the New Orleans Mint.