1624 - Copper standard is introduced
The first copper coins are minted when Sweden introduces the copper standard in 1624. The reasons for this are the shortage of silver and gold due to the prolonged wars, and a desire to maintain the price of copper, which was Sweden's most important export product.
Falu copper mine accounted for 2/3 of Europe's copper supply during the first half of the 17th century. The idea was that by using some of all the copper extracted in the mines for domestic coinage, the volume of copper exported would decline, which would push up the price.
At first, only square-shaped small coins were minted, known as "clippings". But these were easy to reduce in size without anyone really noticing and they were therefore replaced after only a few years with round copper coins.