Back in December, we passed along plans by the U.S. Mint to issue a Baseball Hall of Fame Commemorative Coin. We now know that the set will be released March 27, thanks to the Mint's official Twitter account.
The official U.S. Mint website has the full details on the coins and here's a handy little GIF to give a good idea as to what exactly a curved coin is.
See, the baseball part sticks out like a ball! Outstanding work, U.S. Mint.