Rubellite is an Gemsona created by LaddyJesus. She and her partner Hassonite were exiled from Homeworld when it was discovered that they had been fusing to form Aventurine.
Rubellite is young for a gem, only 70 years old or so, not counting the time she spent in a kindergarten. That and her exile from Homeworld so early are why, unlike most gems, she's not that committed to any one purpose. On the contrary, she is very playful, enjoying many of Earth's games, like chess. Even still, she is very intelligent, and when the time comes to fight, she will come up with a strategy to try and win. Her weapon is a crossbow, but often she will use it for melee fighting. She and Hassonite are great friends, which is why they first fused as Aventurine.