Nicknamed 'Antarc', Antarcticite is in-charge of the winter patrol duty, during that time other gems are asleep. Antarcticite is blunt, perfectionist, judgmental, kind and loves to hug Adamant-sensei but gets embarrassed when seen by someone else. The official character description says that Antarcticite behaves like a soldier and an only child.
Just like the other gems Antarcticite is genderless.