Moontears

Moontears, also known as Prince Martin's "Great Unicorn Treasure", are like eggs. They fall from the sky as shooting stars on the holiday of Starfell. They get buried in the snow on Starscrape Mountain. The unicorns run up the mountain and wake the moontears.

Sophie finds some moontears in Windemere Manor. She wears the moontear necklace and takes it to Arden. After Book 2: Secret in the Stone, the moontears are stolen by Queen Estelle. In Book 3: Fire in the Star, the moontears are woken by Sophie and turn to unicorns.