Did you have any idea how long these conversation hearts had been around? I was looking for some more info and found this on the Necco site:
...the concept behind today's Conversation Hearts got its start when Abraham Lincoln was still President. Mottoes seemed to have come into prominence with cockles, a small crisp candy made of sugar and flour formed in the shape of a cockle or scallop shell. The early cockles contained mottoes, which were printed on thin colored paper and rolled up inside.
In the 1860's, when Daniel Chase, the brother of New England Confectionery Company's founder, Oliver Chase, began printing sayings on the candy. He experimented first with hand tools, and then devised a machine in which the cloth was replaced with a felt roller pad, moistened with vegetable coloring, usually red, which pressed against the die. The die printed the words on the lozenge paste and the double purpose machine cut the lozenges.
Grown-ups were entertained and passed the hearts around at parties. For weddings, there were wedding-day lozenges with humorously foreboding prophecies such as: "Married in satin, Love will not be lasting" "Married in Pink, He will take to drink" and "Married in white, You have chosen right."
The present day Sweethearts® Conversation Heart dates back to 1902. Back then, besides hearts, they also produced various shapes such as postcards, baseballs, horseshoes and watches.