Conversation hearts, the iconic pastel candies featuring phrases like "Be Mine" and "XOXO," have been a significant part of Valentine's Day celebrations in the United States for over a century. Their historical origins date back to 1847 in Boston, where pharmacist Oliver Chase's invention of a lozenge machine paved the way for the production of these sweet treats. By 1866, his brother Daniel Chase enhanced the candies by developing a process to imprint messages directly onto them, transforming them into a personal, romantic gift that couples could exchange.