The Buck Starts Here

The U.S. Mint performed some neat tricks to make a golden dollar

Poor Susan B. Anthony. A pioneering 19th-century advocate of women’s rights, she suffered the misfortune of having her stalwart visage stamped on a wildly unpopular U.S. coin. Because the Susan B. Anthony dollar looks confusingly like a quarter, it never won the public’s acceptance.

The coin shows Sacagawea carrying her son. Some people have questioned the accuracy of the portrayal, noting that the Shoshone carried their infants on cradleboards facing backwards. Historians and other experts consulted by the U.S. Mint have said that at times during the journey, Sacagawea probably did carry Jean Baptiste in a sling. Lucky for the mint; the design is more aesthetically pleasing if the baby faces forward. U.S. Mint
The reverse side of the golden dollar coin depicts an eagle–required by the United States Dollar Coin Act of 1997–surrounded by 17 stars, one for each state in the Union at the time of the 1804 Lewis and Clark expedition. U.S. Mint

Now, 21 years after its introduction, the Susan B. Anthony is about to retire. On Jan. 27, the United States Mint shipped new golden dollar coins simultaneously to Federal Reserve Banks and the discount megastore Wal-Mart. Last month, the mint began an advertising campaign to introduce the coin to the public.

The new dollar is different from the Susan B. Anthony, inside and out. No stern mugshot adorns this coin. Instead, the luminous face of Sacagawea, the young Shoshone woman who guided the Lewis and Clark expedition from 1804 to 1806, gazes from the coin’s face. She carries her sleeping infant son, Jean Baptiste, on her back. Its unique color and other features distinguish this coin from the Susan B. Anthony and the quarter.

The choice of metals used in the golden dollar took as much, if not more, work than the design did. “We pulled off a trick, a really nifty trick, when we chose the alloy for this coin,” said Philip N. Diehl, the director of the U.S. Mint, addressing the National Press Club in Washington, D.C., on Feb. 23. That trick saved companies from the expensive task of retooling millions of vending machines and coin-operated devices around the country.

So far, it seems that the lessons learned from the Susan B. Anthony fiasco have paid off. The mint expects that within the first 3 months of release, demand for the Sacagawea dollar will reach more than half a billion coins, says Diehl. It took the Susan B. Anthony 14 years to reach that demand. The mint “cannot be satisfied with proving that the golden dollar is a beautiful racehorse,” he adds. “Our goal is for it to become the workhorse of American coinage.”

Most successful

Even though consumers deemed the Susan B. Anthony a dismal failure, it’s actually the most successful dollar coin the country has ever had. Nine hundred million are in circulation. The United States minted silver dollars sporadically between 1794 and 1935 and copper-nickel dollars bearing the image of Dwight D. Eisenhower from 1971 to 1978. In 1978, Congress authorized the minting of the Susan B. Anthony.

Why does the country need a dollar coin? For the mint, it’s a good investment. The Sacagawea dollar coin, which costs 12 cents to make, can last 30 years. A dollar bill, costing 3.5 cents, heads for the shredder after about 18 months. A popular dollar coin could earn a hefty profit for the U.S. Treasury, just as a successful product does for a private company.

Coins also work a lot better than bills in vending machines. “Paper money is fickle,” says Thomas E. McMahon, vice president and counsel for the National Automatic Merchandising Association in Chicago. “Too many times, it’s not read properly, which results in a lost sale or at least a frustrated customer.” Also, machines give coins as change more easily than bills.

The escalating price of vending machine items and the dwindling supply of Susan B. Anthony dollars minted in 1979 and 1980 prompted Congress to enact legislation authorizing a successor. The United States Dollar Coin Act of 1997 specified that the new dollar coin be golden in color, have a distinctive edge, and be the same size as the Susan B. Anthony. In other words, the coin has to look and feel different to consumers but resemble the Susan B. Anthony closely enough to fool vending machines.

Importantly, the act did not eliminate the dollar bill. Legislation that would have done that “sat in Congress and went nowhere for about 15 years,” Diehl says. The proposal to make a coin along with the current dollar bill “flew through Congress [and] landed on the president’s desk within 4 or 5 months.”

Golden luster

The Sacagawea coin has the same luster as 14-carat gold, though it does not actually contain the precious metal, says Michael White, a U.S. Mint spokesperson. It has a wider border than other coins do and a plain, smooth edge just like the nickel. It’s 26.5 millimeters in diameter and weighs 8.1 grams, making it slightly larger than the quarter.

Testing done by the mint shows that consumers, both sighted and visually impaired, can pick out the coin by feel without trouble, says White.

Whereas the coin must be distinctive to people, the country’s 15 million vending machines need to treat it the same as the Susan B. Anthony. Had businesses been obliged to retune all of their machines, says McMahon, many would have been unwilling to do so, which would in turn have hurt the coin’s success.

A new alloy developed by Olin Brass in East Alton, Ill., which has supplied the U.S. Mint with materials since 1964, allowed Sacagawea to masquerade as Susan B. Anthony. Vending machines identify a coin by its weight, size, and so-called electromagnetic signature. Vending machines typically test a coin’s electrical conductivity by passing an alternating current through it and measuring the induced magnetic field, says Dennis R. Brauer, Olin’s vice president of technology.

Metallurgists at the mint could match the Susan B. Anthony’s size and weight easily, but duplicating its electromagnetic properties proved to be much trickier. That signature depends on both the type of metal and the construction of the coin.

Like all silver-colored U.S. coins, the Susan B. Anthony consists of a pure copper core sandwiched by two layers of a copper-nickel alloy. The material is durable, easy to stamp with a design, and tarnish-resistant. To make test coins, the mint asked Olin Brass to provide about 25 alloys in different thicknesses—a total of more than 30,000 samples. They hoped to find a coin that would duplicate the Susan B. Anthony’s electromagnetic signature.

Nothing worked. “All the golden color alloys had three times too much conductivity,” Brauer says.

What’s more, different companies use different frequencies of alternating current in their coin acceptors, compounding the problem. “The higher the frequency, the shallower the penetration into the coin,” Brauer explains. “At higher frequencies, you measure only the surface conductivity. Lower frequencies penetrate into the core.”

Metallurgists at the U.S. Mint tried many different combinations of alloys and coin constructions, trying to offset the higher conductivity with different metal-layer thicknesses. “They could easily match it for one machine, but it was not universal,” Brauer notes.

Last May—3 months before manufacturing was to start—the mint was ready to concede and go with an alloy that did not satisfy the electromagnetic requirements. Researchers at Olin Brass, however, had a final brainstorm. They knew of some manganese alloys that have low conductivities, but these materials are pink, Brauer says. By adding enough manganese and zinc to copper, the researchers thought they might get a golden alloy with the right electromagnetic properties.

The strategy worked. After adding some nickel for tarnish resistance, they told the mint about the brand-new material. “I sent them five sample coins, then eventually a 40,000-pound lot, and the rest is history,” says Brauer.

The final alloy consists of 77 percent copper, 12 percent zinc, 7 percent manganese, and 4 percent nickel. The pure copper core makes up half of the metal in the coin, with the two layers of manganese brass each taking up one-fourth of the thickness.

For coins, counterfeiting isn’t a big problem—it’s more profitable for a crook to print fake twenties and fifties. Vendors do worry, however, about unscrupulous customers feeding slugs, or fake coins, into their machines.

The sandwich design as well as the unique properties of the alloy make slugging difficult to carry off. Olin Brass casts the material in 10-ton ingots, then squeezes them between rollers to get them down to the proper thickness. “It’s not something you can do in your garage,” Brauer notes.

Because the new dollar costs only 12 cents to make, Diehl notes, the mint recovers a healthy 88-cent profit on every dollar coin it sells. The Sacagawea dollar will help the U.S. Mint continue to make a lot of money—in more ways than one.

Public comment

In designing the coin, the U.S. Mint took the unprecedented step of soliciting comments from the public. More than 130,000 people sent their ideas via letters, faxes, and electronic messages. In June 1998, a design advisory committee that reviewed the input recommended that the dollar coin honor Sacagawea.

The mint then invited 23 artists to submit designs. After consulting representatives of the Native American community, historians, artists, educators, and the public, the mint chose sculptor Glenna Goodacre’s design. For the eagle on the coin’s reverse side, it chose a design by mint engraver Thomas D. Rogers Sr.

The Sacagawea design is “surprisingly effective,” says John M. Kleeberg, curator of modern coins at the American Numismatic Society in New York. “So much of the stuff produced by the U.S. Mint has been terrible. The modeling of Sacagawea is nicely done, and the pose is an unusual one. We don’t know what she looked like, but [on the coin] she doesn’t look like a cold goddess.”

Coins with simple designs continue to look good even as they wear down, Kleeberg says. The new golden dollar follows that precept.

People seem to be taken with the Sacagawea dollar, Diehl says. “Banks and retailers that never indicated any interest in this coin and had never ordered a single Susan B. Anthony coin wanted it immediately because the American people wanted it. . . . It really is a stunningly beautiful product. . . . It connects with people, and they want to have and hold it.”

People who want to pocket the new dollars can get them a variety of ways. The mint sells the coins on its Web site (, banks and Wal-Mart stores carry them, and a few lucky breakfast-cereal eaters might find them in boxes of Cheerios.

The U.S. Mint predicts that demand for the golden dollar will reach 1 billion coins by the end of the year, more than the Susan B. Anthony could muster in its entire lifetime.

And though there’s no gold in the circulating dollar coin, collectors will be happy to know that the mint will start making a 22-carat-gold version this summer—for anyone who can come up with considerably more than a buck.

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