Worth its weight
The mark has been money in such countries as Germany, Finland and Sweden. Originally the mark was a unit of weight, about 210 grams, which was used to weigh precious metals. A coin was made of something valuable such as gold, silver, copper or iron. If the coin was a silver mark, it was also supposed to contain a mark’s weight in silver.However, the value of the coins gradually worsened, because it was common practice to reduce their weight by adding copper to the silver.
During the Middle Ages this fraud was not even kept secret. Genuine silver and coined silver became worth two different amounts. In the 1300s, something might cost either 100 marks of silver by weight or 500 marks in coin. People simply presumed that there was only one-fifth as much silver in the coins as there should have been. Two hundred years later, the difference was even greater, with 1 mark of silver by weight or 13 marks in coin.
Over time, the link between the mark as a unit of weight and the mark as a unit of coinage disappeared. However, there was still silver in Swedish 1 kronor coins all the way up until 1968. Then the silver was removed, because the silver value had become greater than the coin’s value. The new coins were then made of a mixture of copper and nickel. As of 2016 they are made of steel with a copper overlay.