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1921 Missouri Centennial Commemorative Half Dollar Coin

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1921 “Plain” Missouri Centennial Half Dollar Coin.

1921 “Plain” Missouri Centennial Half Dollar Coin.

Bicentennial of the State of Missouri

The year 2021 marks the 200th anniversary of the admission of the state of Missouri into the Union as the 24th state. Like Kansas, which became a state 40 years later, slavery was a contentious issue during the formative years of both states. In the case of Missouri, which became a state on August 10, 1821, compromises had to be reached within Congress to maintain the balance of slave and free states in the Union. In what became known as the Compromise of 1820, orchestrated by the veteran statesman Henry Clay, Missouri entered the Union as a slave state and Maine entered as a free state, thus keeping the balance of 12 free and 12 slave holding states in America.

Though the compromise solved the problem of maintaining this delicate balance, the dispute served as an omen for future sectional tensions, so presciently expressed by the elder statesman Thomas Jefferson when he said the compromise was “a [death] knell for the Union.” The Civil War would nearly prove Jefferson correct.

1921 Missouri Centennial Half Dollar Coin

To celebrate the centennial of the state of Missouri, Congress authorized the striking of 250,000 half dollar commemorative coins. The Missouri Centennial Exposition forwarded designs to the Commission of Fine Arts to prepare a mold. The medalist and sculpture Robert Aitken, best known as the designer of the 1915 Panama-Pacific International Exposition round and octagonal gold $50 coins, was appointed to prepare the design. The obverse of the coin features the portrait of the frontiersman and Missourian Daniel Boone, an 1821-1921 date, and the legend. The reverse has figures of Boone and a Native American against a starry background, the legend, and the word “SEDALIA” incused below. The coin was struck for distribution to the public at the Missouri State Fair and Exposition held in Sedalia, Missouri, during August of 1921. The Missouri Centennial Committee branch of the Sedalia Chamber of Commerce was the custodian of the coin issue, and they appointed the Sedalia Trust Company for distribution.

In order to sell more half dollar coins, which sold for a dollar each, the chairman of the exposition, James Montgomery, requested that 5,000 of the coins have “2*4” added to the obverse field to signify Missouri as the 24th state to enter the Union. The hope was that two varieties of the coin would prompt collectors to purchase two coins rather than just one. Mr. Montgomery was probably disappointed with the final sales numbers for the coins, as many remained unsold and had to be melted.

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1921 “2*4” Missouri Commemorative Half Dollar Coin. The 2*4 is circled on the obverse.

1921 “2*4” Missouri Commemorative Half Dollar Coin. The 2*4 is circled on the obverse.

Collecting the 1921 Missouri Commemorative Coin

Collectors looking for a Missouri half will normally encounter coins AU to MS-63 condition. They were typically weakly struck, resulting in a flatness on the central portions of Boone on the obverse and the torsos of the two figures on the reverse. Well struck examples in a high grade like MS-65 will cost around $2,000, more if the toning is exceptional. For circulated grades, such as XF or AU, they typically sell in the $400 to $500 range. The rarer 2*4 variety sells for about a $100 premium over the more common Plain variety. A 1921 2*4 variety professionally graded and encapsulated by PCGS sold for $899 on eBay as a Buy-It-Now. The coin had a CAC sticker.

A Question of the Exact Mintage of the Coin

The exact mintages of the coins are still a question of debate for numismatists. In July 1921, the Philadelphia Mint struck 50,028 coins, of which the first 10,000 bore the “2*4” designation. The balance of the mintage was of the “Plain” variety without the 2*4 added. This is where the mintage picture gets a bit murky; advertisements at the time listed the 2*4 variety with a mintage of 5,000, not the 10,000 as reported by the mint. It was thought that 29,600 of the Plain style coins were melted, leaving a mintage of 10,400 or 15,400. The mint retained 28 coins for the Assay Commission. After population studies, modern numismatists believe that approximately 10,000 of the 2*4 coins were issued, rather than the smaller 5,000 number listed in the advertisements.

Over the years, collectors have settled on a reasonable estimate of 9,000 for the 2*4 variety and 11,400 for the Plain. This low mintage for both strikes makes the Missouri Commemorative a scarcer coin among the mint issued commemorative coins. For the sake of comparison, there were over 1.5M 1893 Columbian Commemorative half dollars issued, making it a common commemorative half dollar coin.

Coin Specifications

Weight 12.5 grams, composition 0.900 silver, .100 copper (net weight: 0.361 Troy ounces of pure silver), diameter 30.5mm, reeded edge, mint: Philadelphia.


  • Bowers, Q. David. A Guide Book of United States Commemorative Coins. Second Edition. Alabama: Whitman Publishing LLC, 2017.
  • Boyer, Paul S. (Editor). The Oxford Companion to United States History. Oxford: Oxford University Press, 2001.
  • Taxay, Don. An Illustrated History of the United States Commemorative Coinage. New York: Arco Publishing Company, Inc., 1967.

© 2020 Doug West

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