1644 - The world's largest coin
The first copper coins were minted when Sweden introduced the copper standard in 1624. As copper is worth less than silver, large plates of copper were needed to replace small silver coins. The largest copper coin weighed almost 20 kilos.
Sweden had problems selling all the copper produced in the country. This was an important reason behind the minting of a great number of large copper coins up until 1644. For obvious reasons, the coins were not particularly convenient, which contributed towards the first banknotes being issued in the later part of the 1600s.