Tanzanite is one of the more melancholy-seeming gems, similar to the Lapis Lazuli we see in Steven Universe. Most of her kin prefer to feel as little emotion as possible, but she is different, keeping things bottled up inside until she explodes, which is typically during a fight. She just suffers quietly, not wanting anyone to be concerned about her. She bears the scars of her past, and often has flashbacks relating to her troubled history, triggered by various stimuli such as certain places, words, actions, voices, objects, and people. Tanzanite was an ally of the Crystal Gems, and before she joined them, she was a poorly-treated servant of Blue Diamond. In her first battle, she was on Homeworld's side, and she was mistaken for one of the rebels, and as a result, was stabbed in the back by a Ruby. Were it not for Rose Quartz, she would have been shattered, and the shards of her gem would be used in "The Cluster." She joined Rose's cause, and when she came to Earth, she had gone traveling, learning the ways of the humans over thousands of years. Eventually, she made it to Beach City, and she made her home in a cavern beneath the temple, only accessible at low tide. She hopes to one day stand against Homeworld in a final battle for Earth, and shatter White Diamond, Blue Diamond, and Yellow Diamond. Tanzanite rarely leaves her cavern, but when she does, it's usually to check on the Crystal Gems. She has yet to meet Steven, Connie, Greg, Amethyst, Peridot, and Lapis Lazuli. Due to her origins, Tanzanite can produce sparks when she feels the need to start a fire. She can manipulate small fires to do her bidding, although this power is difficult for her to control. Her weapon is a shield that resembles that of a templar, made from blue and purple flames. Extreme heat does not affect her, and she can set herself on fire at will. Most of these abilities have been passed down to her half-human daughter, Mariah. The following fusions would be created if she were to fuse with one of the Crystal Gems. Pearl: Amazonite Amethyst: Chaldecony Garnet: Kunzite Steven/Rose Quartz: Violet Quartz Lapis Lazuli: Kyanite Peridot: Azurite
I give all credit to Rebecca Sugar for creating Steven Universe and for creating the Gemsona Creator.