Alexandrite is a gemstone person from the anime and manga series Houseki no Kuni (Land of the Lustrous). Known for their obsession with Lunarians, Alexandrite is the resident expert on these mysterious adversaries, often studying and cataloging their appearances. They are highly intelligent but can become easily distracted when Lunarians appear, leading to erratic behavior. Alexandrite is valued for their knowledge and plays a supporting role, providing crucial information to the other gems during battles.