- The Washington Times - Wednesday, August 27, 2003

When the U.S. Mint opened in 1792, it made 11,173 copper cents in the first year. Today, 750 coins are produced in a minute with high-speed machines.

Although improved production techniques create coins more efficiently than when the U.S. Mint started, the original intention remains the same, says Henrietta Holsman Fore, director of the U.S. Mint in Northwest.

“Coins reflect the values, the character and the history of our nation,” she says. “They are emblems of our civilization. From a very modern point of view, when they end up traveling in our pockets around the world, they are ambassadors for our country.”

This year, the U.S. Mint will produce between 15 billion and 18 billion coins, making an average of $6.5 million a day at mints in Philadelphia and Denver. Because all coins are made for less than their face values, last year the organization made about $1 billion in profits, which went into the General Fund of the Treasury. The average coin can remain in circulation about 25 to 30 years.

Ms. Fore believes a coin renaissance is under way, especially with the release of a newly designed quarter every 10 weeks through the 50 State Quarters program. Also, after the introduction of the European euro in 2002, she says the U.S. Mint has been considering a national coin redesign.

Before any new pattern is stamped on metal, however, John W. Snow, secretary of the U.S. Department of the Treasury, must approve it, says Ron Harrigal, assistant director for design and research and development at the U.S. Mint. For instance, this process was used before the text was changed and the size of George Washington was reduced on the coins in the 50 State Quarters program.

Once Mr. Snow gives the green light, Mr. Harrigal says a three-dimensional, 11-inch circular model is made of the new coin in clay or wax. The model is then critiqued for certain parameters, such as the amount of relief on either side of the coin. The contour on each side needs to be equal so there’s not too much metal on one face.

“When you make the coin, it’s pressed between two negative images,” Mr. Harrigal says. “They are fighting for the metal flow. We need to make sure they are balanced to work in vending machines. The machine must recognize it as balanced to buy a can of soda.”

A plaster copy of the 11-inch model is made, which, in turn is used to make a negative form of the new coin in rubber. The rubber form is used to create a positive, 11-inch model in epoxy.

A transfer engraving machine creates a coin-size copy of the 11-inch epoxy model in steel. The result, called a master hub, is used to press a master die in a negative form. Positive-relief work hubs are made from the master die, and from those work hubs, negative-form work dies are made.

“Work dies make the coins,” Mr. Harrigal says. “We need to make sure we can make 1,000 of these work dies. If you have a work hub crack, you need to be able to make coins from another work hub from the master die.”

The amount of detail on the faces of coins always excites Mr. Harrigal. Although pennies are tossed around as if they are a dime a dozen, he says the patterns’ creators scrutinize the images.

“We look at them with magnifying glasses,” he says. “We ensure the design will look right. The average person probably hasn’t really looked at a penny, nickel or dime lately. They are miniature works of art in metal that are there for people to appreciate.”

All circulating coins, with the exception of the penny, start as a coiled sheet of copper-nickel alloy, which weighs about 3 tons, says Brad Cooper, associate director for manufacturing at the U.S. Mint.

With the penny, the U.S. Mint buys copper and zinc, which is sent to a fabricator that creates blanks, coin-size discs without a design that are ready for pressing. For the other coins, the copper-nickel alloy goes through a cladding process to discourage counterfeiting. During cladding, a copper center is sandwiched between layers of copper-nickel alloy. The materials are bonded together with temperature and pressure, a difficult process to replicate.

This process gives the coin an electromagnetic signature unique to each denomination of coin based on its mass, density and design, which vending machines and parking meters recognize. Because the penny is unlikely to be counterfeited, it doesn’t go through the cladding process.

The copper-nickel alloy is fed into a blanking press, which produces a cut blank. Typically, it makes about 600 strokes per minute, and one stroke makes about 20 blanks. The blanks are taken away by a conveyor, while the leftover material is recycled. The blanks then enter an annealing furnace, which is about 40 feet long and 20 feet tall, where they are heated and softened.

Then they are washed chemically and dried in a 25-foot barrel to remove any oxides. About a ton of metal is annealed, washed and dried in an hour.

Another conveyor moves the blanks to upsetting mills, which takes the cleaned and softened blanks through a process that raises and hardens their edges.

“If you don’t do that, when we make the coin, it will come out like a bottle cap,” Mr. Cooper says. “It would end up getting squished, the design on the coin wouldn’t look like a coin. You can’t control the thickness of the coin unless you run it through the upsetting mill.”

Then, the blanks travel on a conveyor to the coining press, where the work dies are waiting. The soon-to-be-coins are fed into each coining press, which make about 750 strokes a minute.

After the coins are pressed, they fall into a small box attached to the press, which is called a trap. It takes about 10 minutes to fill the trap. An operator checks to see if the details on the coins have been properly manufactured.

If the details on the coins aren’t right, they will be destroyed and recycled. If they are good, the operator releases the trap, which goes to another conveyor that takes the coins to a counting machine, which bags them in large woven bags that each hold about 250,000 coins.

A truck with a forklift takes the bags and puts them on a scale and weighs them to ensure the count is accurate, and then they are shipped to the Federal Reserve in Northwest, the central bank of the United States, founded by Congress in 1913.

Despite society’s use of credit cards and debit cards, Mr. Cooper says people will never grow tired of tangible coins.

“Everyone has them in their car, their pocket, their pocketbook,” he says. “They are used all day, every day, by every man, woman and child in the country. … People still feel a sense of comfort knowing they have coins in their pocket. There is heft to them.”

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