Moissanite is the youngest of the guards, and namely not one- he's officially Putnisite's assistant, but really he's the one protecting him.
Putnisite is the smartest of the gems, but also the weakest and most frail- with only 1 of hardness, he needs help. And the young and strong and extrahard Moissanite is perfect for this job!
Moissanite is short but powerful, almost as hard as a diamond and less breakable (not as unbreakable as Ballas tho..), very able in swordsmanship and with excellent reflexes.
He's somewhat resented about not being a diamond, and unsure if its a good or a bad thing. He's a very unsure young gem- does he want to be a diamond or not? does he want to have fun or be serious and work for Putni all the time? Does he like to play with Demantoid and Crocoite or to train with Kammererite? He doesn't know he can enjoy both... for Moissanite, the world is only black or white.