A United States penny dated 1793 sold at a Heritage auction in Florida (January 7, 2015) for $2.35 million. What makes the one-cent piece so valuable is the endless chain design of linked rings symbolizing the unity of the original 13 colonies. The original 13-link chain was changed to 15 links before the penny was minted. A few months later, the chain was replaced with a wreath.

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