The National Sesquicentennial Exhibition Association was chartered by an Act of Congress in March 1925, tasked with organizing the world’s fair in Philadelphia to celebrate the 150th anniversary of American independence. Though the governing body of the fair was called the Exhibition Association in the authorizing legislation, the event came to be known to history as the Sesquicentennial Exposition, instead.

The same legislation also authorized the creation of two commemorative coins: a silver half dollar and a gold quarter eagle ($2.50). Originally, plans had been made for a whole series of Sesquicentennial coins, including a unique $1.50 coin and coins representing different periods of growth in the history of the United States. However, this was pared back in the final bill to just the half dollar and quarter eagle.

The US Mint’s new Chief Engraver, John R. Sinnock, was tasked with designing the two commemorative coins. Sinnock had taken over the position from George T. Morgan, namesake of the Morgan dollar, who had passed away in January 1925. Sinnock’s initial designs were met with disapproval from the Exhibition Association, which hired Philadelphia attorney John Frederick Lewis to prepare his own sketches. Lewis was a noted patron of the arts and was then serving as President of the Pennsylvania Academy of Fine Arts, but he was not known personally as an artist. Nevertheless, his sketches for the half dollar were accepted and converted to plaster models by Sinnock. Today, both men are often credited with the design of the half dollar, though Lewis’ involvement was not widely publicized for many years. The design of the quarter eagle is Sinnock’s alone.

The half dollar bears jugate busts of Presidents Washington and Coolidge on the obverse. Coolidge’s appearance on the coin was technically illegal, as the law forbade living people from appearing on coinage. The design was approved nonetheless, either in ignorance or in spite of the law, and Coolidge became the first and only President to appear on a US coin in his lifetime. The selection of Washington is also somewhat questionable, as he was not President in 1776 (or even a member of the Continental Congress). The liberty bell is displayed on the reverse.

Sinnock’s obverse design on the quarter eagle is decidedly Art Deco, with a very contemporary-looking Liberty carrying a scroll and torch. The reverse design shows Independence Hall in Philadelphia, where the Declaration of Independence was signed, with a rising sun behind the building. The reverse design for the 1976 bicentennial half dollar is almost identical, minus the sun. This would be the final gold commemorative coin struck by the US Mint until 1984 $10 Olympic commemorative.

Despite attracting more than six million visitors, the Exposition was widely considered a financial failure. Over one million half dollars and 200,000 quarter eagles were struck, but sales were poor. Both the half dollar and dollar were struck in very low relief for unknown reasons and did not strike well. Their unattractiveness also contributed to their sales failure. 859,408 half dollars and 154,207 quarter eagles were eventually returned to the Mint for melting.