DALLAS — A U.S. one-cent piece dating to 1793 has sold at auction for $2.35 million. Dallas-based Heritage Auctions said the penny sold at auction Wednesday in Orlando, Florida.

The penny is known as a “chain cent” because the design on the back is a chain with 13 linking rings symbolizing the unity of the original 13 colonies.

Heritage President Greg Rohan says the copper cent is rare because the design was changed soon after production started in March 1793. He says critics at the time thought the chain evoked an image of slavery. A wreath replaced the chain in later pennies. Rohan says the buyer wishes to remain anonymous.