New York—Zales, a Signet Jewelers-owned banner, released its new collaborative jewelry offering with candy brand Sweethearts ahead of Valentine’s Day, selling out in less than 48 hours.

The “Zales x Sweethearts” capsule collection reimagines the heart-shaped conversational candies synonymous with Valentine’s Day as limited-edition mystery charms.

The heart-shaped charms are crafted in 10-karat yellow gold and framed by 0.10 carats of lab-grown diamonds.

Each charm comes in a mystery blind box that the wearer must open to discover which one of the three classic Sweethearts candy sayings is engraved in the center, “Ooo La La,” “Amore,” or “XOXO.”

Growing up, Sweethearts candies were the tiny love notes you waited to receive—passed across desks, tucked into cards, or shared with friends. With this collaboration, Zales said it seeks to turn the nostalgic phrases into symbols of self-love, confidence, and personal expression.

The pieces also feature a hinged clasp bail to easily affix them to different necklace and bracelet styles. This allows the charms to be more versatile and personal, said Zales.

The collection follows Zales’ announcement last year that it would take a more playful approach to fine jewelry.

“Growing up, Sweethearts were little affirmations you loved to give and hoped to get,” said Amanda Rather, senior director of marketing at Zales.

“With Zales x Sweethearts, we wanted to flip that idea and create something fun and nostalgic that reminds customers the most powerful affirmations are the ones they give themselves. These charms are about joy, confidence, and celebrating who you are.”

The Zales x Sweethearts collection’s mystery heart charms were available for $49.99 on the Zales website.

The limited collection launched last week and sold out in less than 48 hours.

Identical, unengraved gold heart charms are available on the Zales website for the original retail price of $299.99.