Dr. Universe: How are coins made? -Dahlia, 10, Olympia, WA
In the United States, pennies, nickels, dimes, quarters, and other coins are made through the U.S. Mint. It turns out, they’ve been making a lot more coins than usual during the global pandemic. But more on that in a moment.
It takes both science and art to make coins. Coins are made from metals that have been mixed together. We call these kind of metals alloys. The very first coins in the world were made thousands of years ago in Turkey from electrum, an alloy of gold and silver. A penny is made from an alloy of copper and zinc.
According to the U.S. Mint, an artist will design the coin with all its details. Then sculptors create a model of the coin in clay or using a digital model and use it to make a plaster cast.
People scan the plaster cast using a computer and the computer’s software helps cut the coin design into the end of a metal cylinder. The metal cylinder is used to create more stamps, or dies, that will be used to press the coin design into metal.
Meanwhile, a machine cuts out flat circle shapes from sheets of metal. The circles are called blanks. The blanks heat up, get a bit soft, cool, go through water, and dry.
They go through a machine that raises the edges of the coin before going through another machine that presses the design into the coin.
Finally, the coins are bagged and shipped out to banks. We use them as we buy different things or do laundry at the laundromat.
Each month the U.S. Mint produces about 1 billion coins, which are made in Philadelphia, Pennsylvania and Denver, Colorado.
But because people are trying to prevent the spread of the novel coronavirus, they haven’t been exchanging many coins lately. There are fewer coins moving through the economy.
That’s what I found out from my friend Elizabeth Reilly Gurocak, an economist at Washington State University. She’d been noticing a lot of signs at restaurants and supermarkets informing customers that the country is having a coin shortage.
Your question even inspired her to start collecting coins from around the house and from family members. She takes the coins to counting kiosks at stores or to the bank to exchange for paper money.
“I’m going to start paying for things with coins just to put them back in the economy,” she said. “I’m going to be like the coin fairy!”
To help add more coins to the economy the U.S. Mint also plans to make about 1.65 billion coins each month for the rest of the year. You can help with the coin shortage, too.
“Empty those piggy banks,” Reilly Gurocak said. “Bring coins to the bank to exchange for paper money, buy things with coins, or take them to coin kiosks. We can solve this problem together.”
With help from my friends at Washington State University, we’re investigating tough and smart questions from curious kids around the world.