Blue Diamond

"How curious. I'm impressed by humanity's ability to survive in the wild. What a strange planet, where else would a being as fragile as a human live? While a being as powerful as a Diamond, perish? This is where it happened. Where she was broken."

- Blue Diamond to Greg. "You cannot fathom how much I've mourned. What thousands of years of grief has done to me!"

- Blue Diamond, before unleashing her pathokinesis. "But this is what you wanted. You begged us for a colony of your own. And now, all you want to do is be rid of it. First thing, too many organics, then their cities would be too difficult to dismantle, and now, now these Crystal Gems? We're tired of your excuses, Pink. This Rose Quartz can't hurt you. You can't be swayed by a few unruly gems. Enough! You must understand. You... are a Diamond. Everyone on this planet is looking to you. You don't even have to do anything. Just smile, and wave. Show everyone you are unfazed by this little uprising. Your gems will fall into line, and these Crystal Gems will be no more. As long as you are there to rule, this colony will be completed."

- Blue Diamond to Pink Diamond.

Blue Diamond is one of the main antagonists of the Cartoon Network series Steven Universe, along with Yellow Diamond and (supposedly) White Diamond. She is one of the Gem Matriarchs on Gem Homeworld and a member of the Great Diamond Authority ruling over Homeworld. Blue Diamond was apparently responsible for overseeing an attempted colonization of Earth, and later, the attempts to quell the Rebellion of the Crystal Gems.

She is voiced by Lisa Hannigan.

Appearance
Blue Diamond has a massive size and height due to her being a Diamond. Her hair is a very pale shade of blue, appearing as off-white and also together in the front to reveal her gem. She has a gaunt face, full lips, and a straight nose. She also possesses large, slanting eyes with light blue irises and diamond-shaped pupils, thin, black eyebrows, and three black markings on the lower portion of her eyes resembling eyelashes. Her gemstone is located on her chest, and she wears a long, navy blue cloak. Underneath her cloak, she wears a navy blue cowl. She also appears to be slightly shorter than Yellow Diamond, who herself wears heeled boots.

Personality
Blue Diamond's debut portrays her as a very good-natured and mellow Diamond who treats high-ranking members of her court with respect. According to Holly Blue Agate, Blue Diamond has a reputation for mercy, sympathy, and forgiveness. "Saving" Greg from the threat of the Cluster after taking a liking to him, unaware that the Cluster is formerly inactive, demonstrates this. However, as with Yellow Diamond, her true nature may be at odds with her reputation, as she sentences Ruby to shattering for accidentally fusing with Sapphire while trying to do her job and saving her by accident. However, it is unknown if her personality has changed over the millennia after Pink Diamonds death. Blue Diamond's temperament appears to have changed significantly in the 5,000 years following the death of Pink Diamond. She is currently in a state of great depression, still mourning over the shattering of her fellow diamond.

She is unable to let go of the past, becoming fixated on preserving Pink Diamond's legacy. Her efforts to maintain the late diamond's zoo, save Earth specimens from the Cluster's emergence, and her refusal to shatter the rose quartzes that once served under Pink Diamond shows this behavior. She continues to regard the Earth as Pink Diamond's colony, and, due to being unaware that the Cluster is bubbled, is visibly saddened by the fact that the planet will eventually be destroyed. Additionally, Blue Diamond seems to misunderstand humans, given by how she was surprised that Greg was able to comprehend and sympathize with her pain of losing a loved one. As shown in the episode "The Trial", Blue Diamond is extremely opportunistic, diplomatic, and dexterous. Against Yellow Diamond's wishes, she allowed Steven to continue making his case during his trial, though she did lose her temper when his recounting of events differed. She nonetheless seemed to want to hear Blue Zircon's theory on how and why Pink Diamond was shattered. When Yellow Diamond snaps and poofs both Zircons present at the trial, Blue Diamond confronts her and scolds her for not having enough restraint to hear the case out.

This shows that Blue Diamond may be as merciful, forgiving, and sympathetic as her gems claim – at the very least, she certainly has a greater respect for due process and an interest in the truth.

Powers and Abilities
Like all her subjects, Blue Diamond has the standard abilities of a Gem, those including: Enhanced condition, the ability to not age, and, potentially, shapeshifting and fusion. However, she has a greater amount of power within due to her status as a Diamond and member of the Great Diamond Authority.


 * Aura Projection: The Diamonds can project an aura around them that they can control, they can either radiate it from their entire bodies or emit it from specific parts of their bodies, usually their hands. Blue's aura is blue and has water-like properties. Though intangible, Blue was able to break Lapis' water chains from her hands upon coating her hands with her aura. She can use this as an offensive ability in both the physical and mental plane, as seen when she was able to focus her aura and attack Steven as he was projecting.
 * Radiated Pathokinesis: In addition, Blue Diamond can engulf a large area with her aura which induces sorrow to anyone exposed to it. The induction is powerful enough to cause Gems exposed to the aura to break down and cry immediately unprovoked, even affecting Yellow Diamond to a small degree. When she unleashed her grief over Pink Diamond's death, she instantly rendered the Crystal Gems unable to fight. The aura is also potent enough to split all but the most stable Gem fusions that get caught in it apart, as Alexandrite came undone as soon as she was affected by the aura, while Garnet remained whole. The level of resistance to the ability varies. Non-human animals are apparently not affected, as demonstrated by Lion during Yellow and Blue's attack on Earth. Humans can still be affected as long as the aura is strong enough, as Connie was immune to Blue's first attack but collapsed in tears on her next attempt. Gems who feel that they have endured emotional trauma worse than the feelings induced by the aura can resist it almost completely, as Lapis Lazuli barely shed a tear upon being hit by the aura. It's unknown if this ability is limited to Blue Diamond's sadness or if she can project other emotions.
 * Concussive Blast: Blue Diamond is able to concentrate her aura at a single point outside her body to launch long range energy blasts at her opponents.
 * Corruption Induction: Though the attack was meant to obliterate the Crystal Gems on Earth after Pink's supposed shattering, Blue, Yellow, and White Diamond's collective powers instead corrupted the remaining Gems on Earth.
 * Energy Projection: She is shown to have some form of energy projection power that she uses for battle. The energy can be molded into different projectiles, from spheres to a hail of lasers, or combinations thereof.
 * Enhanced Strength: She is able to break Rose's sword with just the snap of her fingers and throw the barn off of her in a fit of rage. However, this might just be a simple matter of physics due to how large she is.

History
Blue Diamond is one of the members of the Great Diamond Authority alongside Yellow Diamond, Pink Diamond and, presumably, White Diamond. As the matriarchs of Gem Homeworld, she was in charge of colonizing planets for Gem colonizations and expansion.

Season 2
In "The Answer" Blue Diamond appears on-screen for the first time in a Garnet's story narrating how Ruby and Sapphire met each other. It is revealed that she was once the supervisor of the colonization of Earth following the death of Pink Diamond at Rose Quartz's hands. To make sure the progress of colonization was completed, she had a Sapphire predicting the further events to come. However, when Ruby risked her life to save Sapphire's they fused into Garnet and gave enough time for Rose Quartz and Pearl to escape from the battle arena. When this happened, Blue Diamond angrily threatened Ruby that she would be shattered for fusing with one of her court members and for letting the rebels escape. However, Sapphire took Ruby from the hand and left the arena falling to the earth surface in time. Blue Diamond was never seen again through the episode after that. In "It Could've Been Great", Blue Diamond's mural is seen on the moon base alongside Yellow, White and Pink Diamonds' and is mentioned by Peridot too.

Season 3
In "Back to the Moon", Blue Diamond's mural is once again seen on the moon base when the Crystal Gems and the Ruby Squad went to visit the place.

Season 4
Blue Diamond appears in "Steven's Dream" in her first onscreen appearance, Blue Diamond returns to Earth one last time to pay her respects to Pink Diamond before, as she believes, the Cluster will emerge, unaware that Steven had contained the superweapon months earlier. Blue Diamond expresses regret over how she should have done more, and wonders what Pink Diamond would think of the Cluster destroying her colony. After Greg reveals himself, Blue Diamond asks her Pearl to bring Greg to her. She then states how she is impressed by humanity's ability to survive in the wild and remarks on the irony that a fragile human can survive on Earth while a being as powerful as a Diamond can perish. When Greg tells her that he also lost someone close to him, Blue Diamond is surprised that a human can sympathize with her, and is glad that she can save Greg from the Cluster. She forcefully takes Greg and boards her ship with the goal of bringing him to Pink Diamond's Zoo.

In "Gem Heist" Holly Blue Agate reveals that after Pink Diamond was shattered, Blue Diamond took over her Zoo in an attempt to preserve her legacy. Blue Diamond and Holly Blue have been maintaining the Zoo since Era 2 began.

In "That Will Be All" Blue Diamond returns to the Zoo to mourn alongside a room full of bubbled Rose Quartzes. She is shocked to find Yellow Diamond entering the room, and tells her that she just wants to cry alone. Blue Diamond listens to Yellow Diamond's song, comforts Yellow when it ends, and is greeted afterward by Holly Blue Agate and the Crystal Gems. Blue Diamond does not understand what Holly Blue means by Sapphire's "special delivery". Once Sapphire lies, and tells her that she foresaw Blue Diamond requesting more humans for the zoo, Blue Diamond believes her, and is sad to announce that there is limited time to retrieve more humans due to the Cluster.

Season 5
In "The Trial", Blue and Yellow Diamond attend the trial of "Rose Quartz" (Steven) after he is brought to Homeworld by Aquamarine and Topaz. After arriving at the trial, Yellow Diamond states that they should shatter Rose Quartz just for how ugly her new form is, however, Blue Diamond states that she wants to hear Rose's case and wants to know what she thinks they will do to her, because she wants to do something worse. After Eyeball comes in as a witness and does massive damage to Rose's case, Blue Diamond, unlike Yellow Diamond, opts to hear out the defense anyway. After Steven confesses to shattering Pink Diamond, Blue Diamond demands to know how, and when Steven doesn't recall exactly how it happened, Blue shouts at him, telling him that Rose used a sword (also using her Pathokinesis to make everyone in the room cry).

After the recess break, Blue Zircon, upon having the sudden realization that Pink Diamond being shattered by Rose Quartz doesn't make sense, presents Blue Diamond's Palanquin to the Diamonds and asks where Pink Diamond's Pearl, Sapphires and other gems were to protect her or predict Rose's arrival, coming to the conclusion that another Diamond was the only gem that could have gotten anywhere close to Pink Diamond without anyone being alarmed, although her and Yellow Zircon forms are destroyed by Yellow Diamond immediately afterwards. Blue and Yellow Diamond then get into an argument over the point of investigating Pink Diamond's death, leaving Steven and Lars to escape using the Palanquin.

In "Your Mother and Mine", Blue Diamond's silhouette is briefly seen along with the other diamonds' silhouettes. Later in the flashback, after the Crystal Gems were formed, Pink Diamond called Yellow and Blue Diamond for help. After Pink was shattered, her silhouette is seen with Yellow and White Diamond's. Their hands are seen in the next shot, launching the Corruption Attack.

In "Can't Go Back", in a dream Steven is having that involves the Diamonds, Blue Diamond tells Pink to stop worrying about the issues on Earth and chides her to just wave and smile in front of her subjects, believing Rose Quartz can't hurt her, before following Yellow out of the room.

In "A Single Pale Rose", Rose Quartz, revealed to actually be Pink Diamond, states that Blue and Yellow don't care about her.

Blue Diamond and Yellow Diamond arrive to the Earth in the episode "Reunited" in order to activate the Cluster. The Cluster emerges but it turns against them. Blue Diamond personally fights against the Crystal Gems. She uses her emotional powers against the Gems, but Garnet is able to keep her preoccupied so that Lapis could drop the farmhouse on her. Whilst the battle continued, Steven is able to speak with both her and Yellow Diamond telepathically, making her finally realize that he was Pink Diamond.

In an "Legs From Here to Homeworld", Blue Diamond expresses delight that Pink is still alive as Steven and tearfully hugs him. Later, it's revealed that she was apparently under the impression that she and Yellow had completely decimated the Gem forces on Earth, most likely meaning that she was unaware of the idea of corrupting Gems until Steven presented Centipeetle to her and Yellow. Later, she, Yelllow, and Steven leave to Homeworld to seek help from White to cure the Corrupted Gems.

Quotes
"How dare you fuse with a member of my court? You will be broken for this!"

- Blue Diamond to Ruby in "The Answer". "Oh, Pink. I'm sorry... I'm so sorry... I should've done more. Yellow says it'll all be over soon. I wonder what you would think. This is your planet, after all. I still think it is."

- Blue Diamond mourning Pink Diamond.

"I'm surprised that a human being is capable of understanding how I feel. It's a shame. There's a geoweapon incubating in your planet that will destroy everything shortly. But you don't deserve that, do you?"

- Blue Diamond to Greg.

"You know, I really shouldn't be here. But I'm glad I came back one last time. I can save one last piece of her legacy."

- Blue Diamond kidnapping Greg.

"I'm fine. Just leave me alone."

- Blue Diamond to Yellow Diamond.

"Yellow, she made them. This is all we have left of her. These Gems, this place, and the Earth."

- Blue Diamond's reasons for preserving the human zoo.

"Why can't you just let me grieve?"

- Blue Diamond to Yellow Diamond.

"I want to know what she thinks we're going to do with her. Because I want to do something worse."

- Blue Diamond. "Not yet. The defense still has to speak."

- Blue Diamond letting Steven defend himself.

"How? How did you do it? How did you shatter Pink Diamond?"

- Blue Diamond questioning Rose (actually Steven).

"It was a SWORD! ...You...shattered her...with a sword!"

- Blue Diamond's Breakdown during the trial.

"Yellow, stop it! Why are you doing this?"

- Blue Diamond after Yellow Diamond poofs the Zircons.

"Can't you restrain yourself?!"

- Blue Diamond trying to calm Yellow Diamond down.

"Rose Quartz. So you escaped Homeworld and crawled back here. This is Pink's world! How dare you use it as your hiding place! Come! Answer for what you've done!"

- Blue Diamond to Steven, whom she believes is Rose.

"I know this sword. This is the sword that shattered her!"

- Blue Diamond before destroying Rose's old Sword.

"Lapis Lazuli? Does every Gem that comes into contact with this planet turn TRAITOR?!!!"

- Blue Diamond, upon seeing Lapis Lazuli again.

"Pathetic! You are nothing!"

- Blue Diamond in response to Steven's declaration to protect his home.

"What good will any of this do? The more I make these Gems suffer, the more I long to see you again, Pink."

- Blue Diamond's inner thoughts.

"It's you... Pink!"

- Blue Diamond recognizing Steven as Pink Diamond.

Trivia

 * Blue Diamond is the first of the Diamonds to be seen on-screen in an episode of Steven Universe.
 * However, Blue Diamond was not the first of the Diamonds to be revealed in Steven Universe media as a whole. The extended theme song reveals Yellow Diamond.
 * Blue Diamond's appearance and her throne appear to be heavily influenced by Indian Muslim culture. Her clothing resembles that of traditional Arab wedding dress, specifically a Henna dress. The frame of her throne has carved geometrical designs for windows, which are a common design in many Indian temples and houses.
 * The largest blue diamond, the Hope Diamond, also originates from India.
 * She somewhat bears resemblance with Connie Maheswaran's mother.
 * Her appearance in "The Answer" is similar to Emperor Palpatine from Star Wars.
 * Despite being a Diamond like Yellow Diamond, the cut of her gem does not exactly match her yellow counterpart, in contrast to other gems of the same type, who appear to share color and cut. However, since the two episodes they appear in were storyboarded by different members of the crew, their gemstones may only look different due to the differing art styles of the crew members, as they appear to be of the same design – a rhombus-shaped decahedron with a rhombus facet and four rectangular facets on the sides.
 * It seems that Blue Diamond wears a cloak while she is travelling, but doesn't wear one when she is on Homeworld and her own places.
 * When she appears for the second time in "Steven's Dream", Blue Diamond's gemstone now bears a closer resemblance to Yellow Diamond's.
 * Blue Diamond's importance is further emphasized, as she has her own palanquin with a curtain in the front and spider legs to move it around on its own.
 * Rebecca Sugar has mentioned that blue colored Gems are mainly diplomats.
 * Rebecca stated that Blue Diamond's character design is meant to look "ghostly" to get the feeling of her mourning, and draws much influence from Martha Graham's Lamentation ballet dance. Her face and hair designs are also inspired by Leiji Matsumoto's art, to make her come across as a "strange presence."
 * Much like Ruby and Sapphire before "Hit the Diamond", all Blue Diamond and Yellow Diamond's main appearances have been in episodes featured in a StevenBomb.
 * According to her mural, Blue Diamond ruled nine planets during the attempt to colonize Earth.
 * Because it has been thousands of years since then, it is possible she controlled over more planets now, although the exact number of them is unknown.