The concept of the Sweethearts Conversation Heart dates back to the 1800s when printed sayings on colored paper were placed in "Cockles," small crisp candies formed in the shape of a scalloped shell. In 1866, Daniel Chase, brother of Oliver Chase, who founded NECCO in 1847, invented the process whereby the sayings could be printed directly on the candy.

The Sweetheart recipe remains the same since the candy's inception. Once originally cut in various shapes and sizes such as postcards, baseballs or horseshoes, the hearts had room for long messages such as "Please send a lock of your hair by return mail." Today, NECCO produces small and large Sweethearts offering short and sweet sentiments.

To meet demand for its Sweethearts, NECCO produces approximately 8 billion hearts per year at three manufacturing facilities in the United States. The entire production - roughly 100,000 pounds a day - sells out in just six weeks.