In 1921, Mr. Farren Zerbe’s photograph hit the news wires, holding what appears to be a large loaf of bread. Not so, says the caption:
Farren Zerbe, of Cincinnati, is holding the world’s largest coin, an old Swedish copper plate. Weight, 6 pounds. Worth $4.
There’s a bunch that’s not right about that caption, but it’s not Mr. Zerbe’s fault. In fact, Mr. Zerbe’s influence in the numismatic world is felt in the weight of his namesake, the Ferren Zerbe Award, the highest award given by the American Numismatic Association. This giant coin was one of 30,000 coins in Zerbe’s collection in 1921, and Zerbe wrote extensively regarding coins and coin collecting. Unfortunately, even with that much knowledge he couldn’t count on an AP writer, aiming for the fewest number of words possible, to correctly identify the gray lump Zerbe was holding in the photo. While the ‘Swedish’ part is right, the rest is a little off. The plate Mr. Zerbe is almost worth four dollars, but only due to a spelling error.
Sweden is a land of natural resources, and one of their greater assets is a vast storehouse of copper. Swedish copper mines have been producing large amounts of the semiprecious metal since the 10th century, and although copper didn’t have the high value of silver and gold, its malleability and usefulness for manufacturing did give the metal a significant value. But, as it has been for centuries until today, copper is only worth a tiny fraction of what the same weight in silver or gold is worth. The fledgling United States considered making one-cent coins out of copper, but found that to have a penny’s worth of copper the coin would be much too large to be useful, somewhere between a quarter and a half-dollar in size. Going a hundred times that to make a copper dollar would require a wheelbarrow just to buy lunch.
But Sweden was a copper-rich country, and they had wars to pay for, so they began issuing copper “dalers”, the monetary unit of the time. The copper was rolled out and formed into plates of up to 40lbs of copper worth 10 dalers. The plates were not the sort of thing you carried to the corner store to do your shopping; they were for larger-scale commerce, and as such they are less common than other coins from the same time. Sweden used these to keep their economy above water, and since they were put into use for a couple hundred of years they proved that Sweden could use its copper reserves to successfully maintain the nation’s coffers.
When it comes to the value of copper, the AP writer’s math doesn’t quite work out in the picture above. Six pounds of copper, even at $0.12 per pound in 1921 prices, is worth nowhere near the $4 claimed in the photo’s caption. And, the relative rarity of this kind of plate money means at the time it was worth more than $4 on the collector’s market. The intrepid reporter sent to document Mr. Zerbe’s massive money just heard wrong. The unit of money is the daler, which sounds about the same as the U.S. monetary unit over the phone, and this is a four-daler chunk, a simple mistake if you don’t have the benefit of a fact-checker. The value of the daler changed wildly, both due to the nation’s monetary system and the inherent value of the copper, so each plate is marked with its value at the corners and in the center. Like ‘pieces of eight’ and fictional wire-money, the Swedish plate money was designed to be cut into smaller denominations as needed.
Mr. Zerbe may have bent the truth just a little regarding the rarity of his plate of copper, though: the British Museum still has an intact 8-daler plate larger than the Zerbe example, and other similar coins have been pulled from shipwrecks. And then, if you adjust your definition of coin, the people of Yap have something to show Mr. Zerbe. Any which way you cut it, Mr. Zerbe’s large chunk of copper, marked with its value and the seal of the issuing king, is not the kind of thing you accidentally notice in the change bowl on your nightstand. As an interesting cul-de-sac in the history of sovereign money, it’s quite the unique piece, if only because it is a numismatic rarity that can be displayed nicely on the mantlepiece. This old plate money does show up in the market from time to time, and from what I’ve seen it’s mostly rather corroded examples from shipwrecks or buried in somebody’s back yards. The example held by Zerbe in his photo is a surprisingly nice, clean example of the coin, and despite the errors in the caption, he is right to be proud of his big coin.