What do you think of this fact?
Small change is annoying. It jingles, bulges your pocket and is never there when you need it. In 17th-century Sweden, people had a very different problem: coins you almost needed a hand truck for.
Copper instead of silver
Sweden had plenty of copper from its own mines back then. So it made money out of copper. But because copper is worth far less than silver, the coins had to be huge to contain enough metal to match their value.
Minting small round copper coins was expensive and fiddly. The solution: take whole copper plates straight from the mines and stamp them with official marks. Plate money was born.
Almost 20 kilos in your hands
The first big plates appeared in 1644. According to Guinness World Records, the 10-daler plate weighed 19.7 kilograms (43 pounds) and measured about 30 by 70 centimeters. That makes it the heaviest coin ever minted for circulation. Around 25,500 of them were made between 1644 and 1655. Seven are known to survive today.
Later there were smaller plates worth 8, 4, 2, 1 and half a daler. According to Stack’s Bowers, plate money was minted and traded for more than 130 years, reaching as far as India and the Pacific.
Bonus fact: Since nobody liked hauling 20 kilos of copper around, receipts for deposited plate money circulated instead. According to Guinness, they were among the earliest forms of paper money.
In hindsight, the paper idea was pretty obvious. Anyone who has carried a 19.7-kilogram coin across town would be happy with a slip of paper.
Plate money was common in Sweden until 1776. After that, wallets were allowed to shrink again.