Bismuth is one of the original members of the Crystal Gems. Before the end of the Rebellion, she and Rose had a conflict of interests, leading to them falling out. This ultimately lead to Bismuth being poofed, bubbled, and left inside of Lion's Dimension. Rose then lied to the other Gems, telling them that she went missing in battle. 5,300 years later, Rose's son, Steven, accidentally freed her. After her proposal had been rejected once again, she and Steven fought, and she was poofed and bubbled again by him. This time, unlike Rose, Steven revealed to the others about what happened to her.
Bismuth has a large, bulky body type with broad shoulders similar to that of Jasper. Her head outlines the shape of the rest of her body, with a large jaw and noticeable cheeks similar to Steven. Her hair is styled in several dreadlocks in a mixture of several bright tones, all held back by a lilac headband. She has a periwinkle complexion, and she sports a single tattoo-like marking of a star pattern on her left shoulder in a smoky dark red. Her gemstone is located in the center of her chest and is noticeably concave.
She wears a black apron-like outfit, resembling a blacksmith, with a single brownish attachment and a pinkish-red star-shaped belt around her waist. Her pants are a burgundy color, and she has dark brown boots.
She is Crystal Gems' weaponsmith during the ancient rebellion, Bismuth is passionately devoted to overthrowing the hierarchical structure of Gem society and grateful to Rose Quartz for showing her that an alternative existed. In the show's special hundredth episode, Steven discovers her gem (a bismuth crystal) stored in a bubble in Lion's mane and accidentally frees her. Steven eventually learns that Bismuth was bubbled by Rose as the result of an argument over war tactics: Rose rejected Bismuth's proposed use of a weapon that would permanently destroy enemy Gems, rather than incapacitate them. When the same argument plays out again, Steven is forced to bubble her once more.