The price was very high because the coin was reportedly the only surviving privately owned coin left in the world. It was one of a kind.
The 1933 Double Eagle was designed by a famous sculptor, Augustus Saint-Gaudens, at the behest of President Theodore Roosevelt. Lady Liberty was displayed on one side of the coin while the other side showed the eagle. It was designed as a high relief coin.
President Roosevelt was interested in high relief coins because of their beauty and artwork. The raised design of a high relief coin appears like a 3D aesthetic.
More than 445,000 coins of the 1933 Double Eagle were minted in 1933. However, they were never allowed to be circulated, and eventually, they were ordered to be melted down. As America was in the throes of the Great Depression, the president removed the United States from the gold standard.
A handful of coins were rescued from being melted down. There are 13 known specimens remaining and only one coin is privately owned - the one that sold at auction for $18.9 million.