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Phosphophyllite (フォスフォフィライト, Fosufofiraito), or Phos for short, is the main protagonist and the youngest Gem when the story began. They're weak, brittle - not suited for battle - and their clumsiness makes them difficult to maintain any other roles. Phos has always wanted to be useful.

Phos' initial job was to make a natural history encyclopedia which they progressed very little on. They promised to help Cinnabar find a job suited for them as well.

Phos so far is the only Gem who has had drastic body and personality changes.

From the Official Website :

  • Their hardness is three and a half. The youngest, at three hundred years old amongst the jewels. They are brittle and weak, so they are not suited for battle. They are clumsy and ineffective and cannot do anything, but they are given the job of completing an Encyclopedia -- The first job they've had since they were born.


Phosphophyllite wears a standard winter uniform and black shoes without socks, occasionally accompanied by long black gloves.

Phosphophyllite has mint-green features known by the Gems and the Admirabilis as the Lunarians' favorite color. Their hair is short, originally just beneath the ears, but cut shorter in later chapters to imitate Antarcticite's hairstyle. Over the course of the story, parts of their body are replaced with other gems and metals. They lose their original legs when Ventricosus attempts to trade them with the Lunarians for her brother. After a failed negotiation with the Lunarians, Ventricosus changes her mind and gifts them parts of her brother's agatized shell as a replacement, which gave them mobility unbeknownst to any Gems.

Phos' new legs in the anime

After losing their arms during winter duties, they were replaced with gold and platinum alloy, which made their arms gold in color and Phos larger in size. Their new arms can shift form and become semi-fluid at will. They also use their alloy to replace the heels of their shoes, likely inspired by Antarcticite. Phos carries Antarcticite's broken blade and uses it during patrol and battles. They switch to a normal sword around meeting with Padparadscha.

After losing their head to the Lunarians, it was replaced with Lapis Lazuli's head instead. They wear Lapis' hair in a high ponytail when Cairngorm asks then to change it due to them appearing too similar to Lapis. Soon after, it gets cut short by an arrow during an attack. On the Moon, Aechmea replaces Phos' left eye with a synthetic pearl replacement that emits light in the dark and can't be closed. Phos wears a moon-version of their gem uniform, with sheer sleeves and heels styled like pearls. Phos' powder is replaced with white waterproof lacquer.

After being split in half by Bort, shattered by the others and eventually rebuilt by Sensei 220 years later, Phos resembles a newborn Gem with an angular, rough, and faced body. Their original eye is now missing with only the pearl eye remaining. The right half of their head is missing, and their mouth opens wide with jagged teeth. Their alloy is constantly leaking out of them, and their limbs are spindly and twig-like. They do not wear any clothes during this time.

When returning to the moon, Phos' alloy shifts into spikes around their neck and down their spine, and a hood that resembles a slitted bodhi leaf. Phos wears a one-piece Lunarian outfit with an open front and back and flat heels made of their alloy.


Phosphophyllite displays a change of personality over the course of the series, mainly due to maturing, trauma, and outside influences. This is mainly due to the fact that the Gems are not equipped to deal with trauma. 

Initially, Phos is a young overconfident, clumsy and naive Gem, who is the only one capable of getting away with talking back to Sensei. Many gems describe them as “lazy” and “useless” due to their fragility and incompetence, although Phos does display a drive to help Sensei and the others that’s only held back by their low hardness. Once gaining new legs, they become more capable, but not as much as they wished. There is an underlying way of how Phos acts and speaks about themself that hints at them taking the “useless” and “lazy” comments to heart, and impacting their self-esteem (which is generally what the ice floes repeat back to them). These facts indicate that Phos may have something of an inferiority complex.They settle with what they can do and constantly state that they will try better next time.  

Their drive becomes self destructive in its own sense, leading to them losing their arms and eventually mental stability. Upon witnessing Antarcticite’s abduction, this marks a clear point in change for Phos. Their carefree nature disappears and they are incredibly distraught over the loss. They become reclusive and tend to keep emotions to themselves, although some of Phos' old self shine through from time to time. They begin to show relief as a new drive comes, until the loss of Ghost Quartz impacts them as well and they begin to display more guilt over the loss of any Gem (even when they are not responsible). They begin to outwardly display their initial personality but it becomes obvious that they are keeping emotions to themselves to not disturb others. They do display confidence again, being able to give orders in a stressful situation. 

Phos’s third influence in personality is the attachment of Lapis’s head to replace their missing one, as the two personalities seem to mix. Phos becomes attentive to details and able to strategize more. The bottling emotions remains and becomes worse as Lapis’s personalities adds a more secretive and manipulative nature to Phos. 

The fourth and currently last influence in personality happens afterKongo-sensei reforms them after 220 years. Phosphophyllite shows massive change in personality where nearly all positive feelings and emotions have disappeared replaced by negative emotions, mainly rage and a great desire for vengeance. There is a culmination in Phos's lack of self-esteem where they dream about the other gems belittling them, calling them "useless" and accusing them of "bringing nothing but failures upon failures". From this point, one of Phos's main trait of character, their kindness, disappear entirely and is replaced by hatred for all Earth gems and perhaps even all things. Even Kongo or the Moon-gems aren't safe from Phos's wrath. Forcing the former to pray by means of physical violence and though they consider the latter as ally they don't mind forcing them into action and ordering them in a harsh manner and manipulative toward them. Discarding Diamond's refusal to go to Earth to attack the Earth-gems and manipulating them to go against Bortz. Aechmea states notably that Phos has become very close to an original human by displaying the most human of emotions : desire of revenge. However, Phos has shown some remains of their previous personality through some bits of kindness and love, notably they stated that they were sure that Kongo still loved them which seems to show that it's still important to them.  

An ongoing theme of the series is the continuous change of Phosphophyllite's mental state. Phos’s mental stability deteriorates over the rest of the series, and their self-destruction begins to extend to others rather than keeping it to themself. They become impatient and volatile. 

Character Profiles

Vol. 2:

  • The protagonist. The youngest (300 years old). Just plain weak. Is now trying to help Cinnabar.

Vol. 3:

  • The protagonist. Their body is starting to become a mess.

Vol. 4:

  • The protagonist. Their hands have gone, and it seems like their heart has too. That's all for now.

Vol. 5:

  • The protagonist. Recently, they seem to be hallucinating in bits and pieces.

Vol. 6:

  • The protagonist. From hereon out, they wish to try their best.

Vol. 7:

  • The protagonist, Phosphophyllite...Phosphophyllite? Nonetheless, I'll talk about everyone's hobbies this time.

Vol. 8:

  • The protagonist. Most of the original Phosphophyllite has been lost. Please, bear with them as well.

Vol. 9:

  • The hero of our story. Working hard.

Vol. 10:

  • The hero of our story. Under a lot of stress.

Vol. 11:

  • The hero of our story. Makes a decision.


Natural Historian Arc

Phosphophyllite is introduced as a Gem who wishes to be a fighter but is too weak, brittle, and untalented in many skills. Kongo-sensei summons them one day to tell them he has finally found a suitable job: the creation of a natural history encyclopedia. They have no idea how to go about this and ask the other Gems for advice. Eventually, they are pointed towards Cinnabar, a Gem who stays outside and patrols the beach at night, avoiding the other Gems because of the poison that their body secretes. Phos searches for Cinnabar all day but does not manage to find them.

Resting on a hill, Phos is suddenly attacked by the Lunarians, but Cinnabar appears and drives them off. Both Gems become damaged during the incidence and the resident doctor Rutile repairs them both. Phos learns that the hill where they were attacked is a dangerous place where Heliodor was recently captured. They go back and meet Cinnabar again, learning that the other Gem stays on that hill because they don't want to bother anyone anymore and wish to be taken to the Moon. Troubled by this, Phosphophyllite makes a one-sided promise to help Cinnabar find a fun job that they will enjoy more.

Phos continues to have trouble working on the encyclopedia. They are recommended to speak with Diamond, who is apparently experimenting with a new technique to fight against the Lunarians. Phos goes out to meet them and Diamond recommends that to becomes stronger, they should change from within and do things they normally wouldn't do. Just then, a Sunspot appears, and the Lunarians attack. Diamond shows off their technique: using their sword to deflect the Lunarian's arrows back at them. Unfortunately, this technique is taxing on Diamond, and their arm breaks under the impact of the arrows. Diamond's partner Bort then arrives at the scene and easily defeats the Lunarians before chastising Diamond for their recklessness. Another Sunspot immediately appears but ignores the three Gems and heads directly towards the school, where Kongo-sensei is in meditation and thus unable to fight them.

The group rushes back to the school and Bort easily defeats the second wave of Lunarians, but not before they drop a large shell onto the school ground. A snail emerges from the shell and swallows Phos, digesting and melting them. All attempts to fight the snail end up with the Gem's swords or bodies being melted, but they finally manage to push the snail into the school's salt-water pond, causing it to shrink. It has now become a tiny slug while its large shell sinks to the bottom of the pond. The Gems search for Phos but cannot find them. Diamond sees the slug respond to their calling Phos' name, and believe Phos has been transformed into the slug. They seek help from the other Gems for a way to turn Phos back but are unsuccessful. Finally, Diamond meets with Cinnabar, who expresses doubt at the idea and believes the slug is just an ordinary slug. They also explain that those types of creatures eat rocks and minerals to form their shells. Diamond realizes that Phos has been incorporated into the snail's shell and gathers the other Gems to pull the shell out of the pond, extracting the Gem's fragments from it. After being successfully put back together, Phosphophyllite learns that they are able to understand and communicate with the slug, who calls itself Ventricosus, the ruler of the Admirabilis.

In order to help Phos' problems, Ventricosus suggests they go to the ocean. Kongo-sensei forbids it, but they manage to steal supplies and sneak away on their own. After venturing far underwater, Ventricosus returns to her true form as a humanoid. While traveling deeper into the ocean, she explains to Phos the legend regarding her people, the Gems, and the Lunarians. Ventricosus also tells Phos that her people were captured and are being held by the Lunarians. With the day about to end and both of them far from the land, Ventricosus reveals that this was a trap, made with the deal that a Gem would be offered to the Lunarians in return for the release of her younger brother, Aculeatus.

The Lunarians appear above the ocean's surface and capture Phos, breaking off their legs. During negotiations between Ventricosus and the Lunarians, Aculeatus awakens and manages to regain their original humanoid form, defeating the Lunarians. Feeling guilty, Ventricosus changes her mind about using Phos as a sacrifice to get back the rest of their kin. The two Admirabilis return to the sea after they leave Phos on the shore of the land, giving them two of the spines from Aculeatus' agate shell as a replacement for their legs.

While Phos was lost at sea, the Gems were frantically searching for them, even spending most of the dusk underwater to find them. Phos washes up on the shore in the cove where Cinnabar stays. The latter brings Phos back to the school where the other Gems find them. Angered, Kongo-sensei scolds Phos and relieves them from their job with the encyclopedia.

New Assignment Arc

Phosphophyllite has their legs replaced by new ones made from stripes of Aculeatus' agate spines and quartz. At first, they were unable to use them, as their inclusions needed to adjust to the new material, but very shortly afterwards they find that they can run at an incredible speed, whizzing past the other Gems before they even notice Phos. Unfortunately, Phos cannot control their legs or stop where they want. Yellow Diamond, currently the eldest among the Gems and also the fastest, manages to catch Phos. Kongo-sensei theorizes that Phosphophyllite's inclusions actually had a lot of potential, but due to Phos' fragile structure, they were unable to use their full potential. By attaching the stronger agate legs, the inclusions suddenly had an outlet for their power. Phos, excited at their newfound strength, once again requests that they be allowed to fight. Kongo-sensei asks Obsidian for the lightest blade, which he takes and holds out to Phos. The Gem takes the blade and immediately falls as it is still too heavy for them. Kongo suggests that Phos partner up with Amethyst since they are experts at swordplay. He also asks Phos for a report of the events during their trek in the ocean. Phos, having lost their original legs and thus a third of their body, has also lost a lot of memories with that part. They cannot recall much, but manage to utter the word "human", which causes Kongo to become shocked for unknown reasons. He dismisses the Gems.

Phos trains with the Amethyst twins for a while before a sunspot appears. Showing off to Phos, the twins become careless while fighting the Lunarians, the sunspot is revealed to be the new type with a weapon made using gem parts. The Amethyst twins are shattered while Phos watches, paralyzed with fear. Bort rushes to the scene and defeats the Lunarians, saving the twins. Later, after the twins are reassembled, Phos apologizes to them for not being able to react, but they apologize back for their carelessness.

Winter Arc

Winter arrives and the Gems prepare for hibernation since they cannot function well with the lack of sunlight. Phos questions the need to hibernate since they do not feel sleepy, even though previously they were always the first to sleep and the last to wake. As most of the Gems enter hibernation, Antarcticite awakens to take up winter duty with Kongo-sensei. Phos, who could not sleep, joins them and is allowed to partner up with a reluctant Antarc.

In meeting Antarcticite, Phos reveal that they felt frustration from their last involvement in battle. The fact that Phos couldn't do anything, and that none of the other Gems scolded them, made them want to work harder. They join Antarc in winter duties, keeping the other Gems peacefully asleep and cutting ice floes whose loud noise would disturb the Gems. As expected, Phos is still poor at doing these jobs. Antarc tells them that their weakness is that they don't try to do things they cannot do, in other words, they don't try to go beyond their own limits.

While cutting ice floes, Phos hears voices coming from them. Antarc and Kongo both reassure them that that is normal and that the ice floes contain inclusions much like the Gems do, though Kongo tells Phos that the ice floes simply repeat back what is already in their own minds. At one point, Phos hears the ice floe encourage them to lose their arms in order to gain strength the same way they lost their legs. Phos rejects these thoughts, but the voices jolt them when they mention Cinnabar. Phos slips and falls into the water. Antarc pulls them out and is shocked to find that their arms have been broken off. Antarc jumps into the water but cannot find their arms at all, they have disappeared completely.

They both report back to Kongo-sensei, who is also visibly disturbed. He comforts Antarc, who blames this on themself and suggests they go to the Beach of Beginnings, where Gems are born. They find gold and platinum, which Antarc grafts onto Phos as substitutes for their arms, even though it is too heavy. While their inclusions adapt to the alloy, they start doing strange things on their ow accord, trapping Phos inside a metal cube. During this time, a sunspot appears and Antarc fights the Lunarians. This sunspot is another new type, containing grenade-like fragments made of Pink Fluorite. Kongo-sensei is also simultaneously attacked and trapped by the Lunarians back at the school. Antarc manages to defeat the new type and goes to free Phos from their cube. In the midst of doing so, Antarc is shot by an arrow and shatters; another sunspot had appeared. Phos watches helplessly as the Lunarians collect the pieces of Antarc and leaves. They beg their gold arm to obey their commands and fight, but even then they are unable to stop the Lunarians. Kongo arrives at the scene to find a broken Phosphophyllite, both of them grieving at the loss of Antarcticite.

Spring Arc

After the loss of Antarcticite, Phos take up winter duties completely. They cut their hair short and use the pieces to patch their cracks up as a tribute to Antarc, as well as adopting a more serious personality. Their new gold arms give them incredible abilities and they are able to deal with the Lunarians with ease. As winter ends and the Gems wake up, all of them become fascinated with Phos' new arms and abilities. Bort senses Phos' potential and has them to partner up in order to iron out the flaws in Phos' fighting technique. Diamond is initially shocked at losing Bort as a partner but accepts this change.

The first Sunspot they encounter is a double Sunspot from which Shiro emerges. Neither Bort nor Phos are able to defeat it so they lure it to the school in the hopes that Kongo-sensei will do so. They lose track of it inside the school and search for it with the help of Alexandrite. Shiro finds and fights Diamond, who manages to split it in half but sustains heavy damage and becomes incapacitated. The split parts of Shiro reforms into smaller copies, which Alexandrite cuts down into even more copies, but these are revealed to be small, harmless puppies. The Gems spend the rest of the day gathering all the pups together only to have it reform into the full-sized Shiro when they gather 107 of them. Kongo-sensei comes out and meets Shiro, who becomes docile and obeys him. Phos accidentally hears Kongo call it by its name and starts to doubt him. They have a sudden unthinkable realization that Kongo may be connected to the Lunarians. They meet Cinnabar (who also found the 108th Lunarian) and discuss this, but the latter informs them that all the other Gems are already aware of that, but chooses to believe in Kongo no matter what. Phos returns to the school to find Kongo and the other Gems sleeping beside Shiro. The large moon creature gives Kongo a final embrace before disappearing.

Phos decides to find out the truth about Kongo's relation with the Lunarians, and aims to do so by talking with the Lunarians directly. While waiting for the next Sunspot, they help Rutile find pieces for Padparadscha, who was born with holes in their body so they spend most of their life unconscious. After successfully reawakening Padparadscha, Phos is able to talk with them for a bit before they fall back unconscious. The older Gem advises Phos to be more discreet about the harsh truth, as it could hurt the person who the truth is intended to be hidden from.

Secrets Arc

Phos learns all they can about Lunarians from Alexandrite, who is the local Lunarians expert and always studies them. When the next sunspot appears, Phos catches one of the Moon Person sundries and encloses both of them with their alloy. Phos attempts to talk with the sundry, but it only manages to make a few vague noises before the Amethyst twins (Cinnabar in the anime) dispatches all the Lunarians. Phos decides to search the library for information as well as previous battle journals regarding the Lunarians. There, they meet Ghost Quartz, whose previous partner Lapis Lazuli was also interested in the Lunarians but ended getting captured by them.

Some time afterwards, three Sunspots appear at the same time, a very rare occurrence. Phos, Kongo-sensei, and Ghost Quartz deal with one of them and in their recklessness, Ghost almost gets taken by the Lunarians. Kongo dispatches the Lunarians, but Phos notices that he breaks off pieces of his own body to do so, and has always done so every time he fights the Lunarians. He tells Phos to keep it a secret. Ghost decides to partner with Phos, and during another Lunarian attack, they end up sacrificing themself to save Phos. But Ghost contained another person inside of them, and only the outer one was taken while the inner one is now in full control. This personality is later named Cairngorm, and becomes Phos' new partner.

Cairngorm is initially harsh on Phos as they blame the latter for the loss of Ghost. But during patrol, Phos suffers some sort of breakdown and mistakes Cairngorm for Antarcticite. They try to protect Cairngorm by trapping them in a cage made from their alloy and dragging them off. Hemimorphite, Tourmaline, and Neptunite see them and try to free Cairngorm. Phos' breakdown worsens and their gold alloy starts to crush the rest of their body, breaking it into smaller and smaller pieces. Jade and Rutile arrive and the former punches Phos in half to prevent the alloy from crushing the shards to dust. After Phos is revived, the Gems express concern for them since their composite body structure is unprecedented. Cairngorm acts less harshly towards Phos, but is still rather strict and critical of them.

Phos, Cairngorm, Sphene, and Peridot are caught in a fight with a new type of Sunspot consisting of a game board with small pieces that can break and pick off shards from the Gems little by little. They have incredible trouble dealing with this until Tourmaline and Bort come to the rescue. Phos manages to retrieve the board and pieces, which have seemingly become motionless and reports it to Kongo-sensei. After the Gems leave, Kongo expresses familiarity with the board, which promptly vanishes in the same way Shiro does.

During the next fight with the Lunarians, Phos loses their head, leaving their body lifeless. Cairngorm offers Lapis Lazuli's head as a replacement, troubled by the idea but wishing to make good on their promise with Ghost to look after Phos. When Kongo-sensei is reluctant to accept the plan, Cairngorm offers their own head instead and starts to break it off before Kongo stops them and finally relents. Rutile attaches Lapis' head to Phos' body and the Gems await the results.

A hundred and two years later, Phosphophyllite finally reawakens. They are surprised by their new head, but accepts it easily and think they have become very cute. That night, Phos has a dream in which they meet Lapis Lazuli. The latter explains how a Gem's inclusions can be used to store memories and that Lapis knew of the possibility that their head may be attached to someone else, so they stored their own persona in it. Lapis explains that Phos also has a strong connection to their own inclusions, which allows their own personality to persist despite the changes done to their body. They hint at a way to find the truth about Kongo-sensei, but Phos cannot quite figure it out. Upon reawakening, Phos finds that they now have the ability to think and observe things in great detail, presumably much like Lapis did.

Phos is at a loss about how to proceed learning the truth. They attempt to remember what happened to them during their journey into the ocean, but neither they nor the other Gems can remember, nor will Kongo-sensei reveal any information about it either. During another Lunarian attack, arrows pierce and cut off some of Phos' long hair that was in a ponytail. While searching for the pieces, the Gems find Variegatus, the current ruler of the Admirabilis and successor to Ventricosus. Though clumsy and air-headed, Variegatus eventually helps Phos remember the legend about humans. She also says that she wants to go to the Moon to rescue the rest of her people, allowing Phos to realize that they must do the same to find the truth.

Journey to the Moon Arc

With the help of Cairngorm, during the next Sunspot, Phos manages to trick the Lunarians into believing that they have captured the Gem. Phos is taken to the Moon and at first causes a rampage when they learn the Lunarians are able to talk and act normally just like the Gems do. Phos is easily defeated by Prince Aechmea, the leader of the Lunarians, who then gives them a tour of the Moon as well as reveal information about their history. He reveals that the Lunarians are the impure souls of humans who are trapped in their existence. He also reveals that Kongo was made as a prayer machine to purify them and thus allow them to pass on, but Kongo broke down a long time ago and stopped doing his job. That is why the Lunarians kidnap the Gems he so cherished- in order to persuade him to go back to work. Phos agrees to cooperate with Aechmea and betray Kongo in return for the Lunarians ceasing their attacks on the Gems. Aechmea replaces Phos' left eye with a synthetic pearl one that the Lunarians can use to track their actions. They return to the Land and are given a month to convince the other Gems to leave Kongo.

Phos successfully captures the interest of a few Gems with their stories, but others are suspicious. A month later, Phos returns to the Moon with nearly half the Gems, leaving the remaining ones distraught to the point of shattering. On the Moon, Phos reveals to the others the truth about abducted Gems being crushed to powder and spread over the Moon's surface, causing some of them to shatter from emotional distress. They also speak with Padparadscha, who was taken along and fixed by the Lunarians, though the older Gem expresses their distrust of the situation. Phos asks Aechmea if the crushed Gems can be restored, to which he replies that he will try, but it is not certain if they'll succeed, and that it may take the entirety of their lives to do so.

Prayer Arc

The “Prince” tells Phos that with their current technology they can restore those Gems of hardness 5 and above. Phos is relieved but also distraught, demanding an explanation to why they can't bring back those 4.5 and below. The Prince explains that said Gems would be impossible to retrieve, much less restore; the finely ground bits of these gems would clash with bits of harder ones and sand, thus becoming particles invisible to the naked eye. Simply aggravating the sand around them would cause displacement of the particles, resulting in further disintegration; some may even escape the moon’s orbit, being lost to infinite space. Phos draws a blank, overwhelmed with flashbacks of Antarcticite, as the newly-revitalized Padparadscha laments that Fluorite and Antarcticite are gone for good.

Upon recovering, Phos stages a nighttime raid on Kongo and the School with Cicada, Yellow Diamond and Padparadscha, pretending it was with rage and vengeance for Antarcticite. However, the Gems, now hostile to Phos and company, have concealed Kongo and engage them in combat. Unable to locate Kongo and being locked in a fierce battle with Bort, Phos is forced to divert attention to Padparadscha, who had been brutally massacring the rest of the Gems. The mission is a failure when Cinnabar arrives, covering Bort and Padparadscha in mercury and subsequently incapacitating Phos. Just then 3 Sunspots open, and a large fleet of Lunarians arrives, led by the now-converted Cairngorm. Phos is relieved to see Cairngorm only to be destroyed and collected by them. Cairngorm says to the shattered remnants that Phos would have hesitated if they had not been broken.

The Prince rebukes Phos for failing the mission, causing a coating of mercury in Padparadscha, and putting his new “wife” in danger. He then hands Phos over to Barbata, the Lunarian's scientist, who informs Phos that the restoration of Gems is proceeding much quicker than they expected. Phos is led to the Moon Lab and is awestruck to see hundreds of chambers already restoring Gems. Barbata's explanation is that the chamber aids the Gems’ inclusions to naturally repair themselves, and their presentation of this is the half-reconstructed Red Diamond. Phos gleefully high-fives Barbata, convinced that it was the right way to go, despite everyone’s contradictions.

Phos's happiness is short lived though, as Barbata tells Phos that they have two decisions to make - the first being that when the gems' bodies are restored, they will lose all their memories due to inclusions preserving their energy to save only the most important information - the location of their bodies. Barbata asks not so much for Phos' decision, but for Phos understanding. Phos reluctantly agrees, as Barbata moves onto the second point - Admirabilis eat the dust in order repair and strengthen their shells, meaning their shells are made out of the gems on the moon, and that specimens that separate their shell from their bodies are becoming less common, and most Admirabilis integrate their shells into their bodies or just recrystallize the sand inside their bodies, and as a result, they'd have to kill all the Admirabilis, explaining to Phos that "kill" means that they'd be gone forever. Barbata goes on to say that failed to create synthetic gem bodies and that if Phos consents to the elimination of the Admirabilis they'd have to suppress their reproduction and lead them to a slow extinction, but if Phos, someone the royal family respects and admires, give a direct order to the Admirabilis, they could do it immediately. Phos tells Barbata that they'd like some time to think about it. Barbata apologizes and tells Phos that he'll try to find another way but doesn't expect a better solution to pop up and Phos will have to choose.

Phos is left to come up with a solution to the Admirabilis, however this seems to be resolved by the Lunarians later on. Phos tells the other Gems on the Moon except for Yellow Diamond, Padparadscha, and Cairngorm, that they plan on returning to Earth once again to speak with Sensei. This time they wish to do it alone. This plan is interrupted by the Prince's and Cairngorm's wedding, which Phos and some of the other Gems attend. Phos celebrates in the after party, trying Barbata's food invention for Gems that consists of light. After the wedding ceremony and after party, Phos wakes up to a message that the Prince would like to speak to them. Phos speaks with the Prince, the Prince informing them of the history between the Admirabilis and the Lunarians and why the Admirabilis were taken to the Moon. Phos is then given a ship to go down to Earth alone, held on by the fact that they suddenly feel manipulative towards Sensei when the thought of "He always cared for me" pops up.

The last thought seems to have no resonance however as when they appear next, they are playing a game and the ship lands. Phos sees Hemimorphite and Watermelon Tourmaline when the ship opens, prompting them to tell the two that they come unarmed and with no ill intent, only wishing to speak with Sensei. They are denied this wish when Bort shatters them with their new weapon: a whip. Phos is reassembled but placed in a holding device and cage, surrounded by the Gems who remained on Earth. Sensei arrives and Phos asks Sensei to pray, to which Sensei mentions that no one has ever bypassed the authentications before and begins to start up. The prayer begins but is shortly ended, although the prayer seems to have gotten ridden of Phos's binds and releases them. This angers Phos who begins to reach out for Sensei, but is quickly shattered again by Bort. Their pieces are then scattered and hidden by each of the Earth aligned Gems.

Invasion Arc

Phos is reassembled by Sensei after 220 years, quickly waking up in a feral state and demanding Sensei to pray and holding his hands together to do so. Although this becomes the closest to which Sensei has prayed, it is quickly revealed that this will destroy not only the Lunarians, but the Gems and Admirabilis as well. However this fact is unknown to Phos. Phos is quickly taken down by some of the Gems when their awakening woke others up from hibernation. They are chased through the frozen landscape before hiding in Cinnabar's cave, upon which they find their old clipboard meant for their encyclopedia that Cinnabar had kept. Phos is quickly found by Rutile who nearly shatters them before another ship arrives, carrying (new) Goshenite, Padparadscha, and Cicada. Padparadscha distracts Rutile long enough for Phos to board the ship and is quickly taken back to the Moon.

Upon landing, Phos is greeted by the Moon aligned Gems and the Prince. The Prince demeans them by stating that Phos wished to remain on Earth the last time they had spoken. Phos doesn't seem to notice that statement, speaking that they had failed in making Sensei pray. Phos also says that Sensei cares for them, even after what they had done, but that the Gems are what's holding Sensei back from praying. Phos quickly comes to the conclusion that they must destroy the remaining Gems so that they can make Sensei pray. They are quickly shattered by a new Shiro that was protecting Cairngorm. Barbata is asked to reassemble Phos.

Phos returns to the other Moon Gems before being completely reassembled. They demand to shatter and destroy all Gems, to which Aechmea allows it. They threaten the other Gems to comply with them, to which Dia and Alexandrite agree to do, Alex bringing in Benitoite. Phosphophyllite returns to Earth with Diamond, Alexandrite, Benitoite, and many other Lunarians to start an attack. They consider the attack successful although all their allied Gems are shattered.

After they massacred most of the Gems, including their allies, Phos enters the main hall of the school. While walking over shattered pieces of gem, they are approached by Euclase. They drop to their knees and surrender to Phos. However, after Euclase attempts to reason with them and find common ground, Phos decapitates them, stating that they don't need anyone else. Phos then orders the Lunarians to fire upon a helpless and indifferent Rutile and Padparadscha sitting off to the side. All the while Phos encounter an angry Jade further down the hall. The encounter immediately escalates into an all out fight. Jade is unable to hit Phos at first due to their alloy keeping them away, but Jade breaks through and punches phos in half. Thinking that they have the upper hand on Phos, they go in for a final hit, before getting caught in Phos' alloy. Phos puts them self back together, and begins smashing Jade against the wall several times before holding them up by their neck. Jade apologies for their inability to understand Phos, before the top half of Jades head snaps off and falls to the floor. Phos states that it's too late for that now before dropping the rest of Jade's body on the ground. As they continue walking down the corridor, they are met face to face with the remaining Earth Gem, Cinnabar.



The Gems are generally kind to each other, including to Phosphophyllite, their youngest sibling. Phos is sometimes called Sanhan (三半), meaning "three and a half", a reference to their low hardness level. When Phos was absorbed into a shell, all the Gems are shown willingly pulling it out of the pond it fell into. When Phos was lost in the ocean, the Gems stayed up into the night searching for them and being only slightly annoyed. However, they don't seem to mind the idea of Phos changing into a slug, thinking it's the best for them due to their trouble-making tendencies. Diamond commented once that Phos wasn't too popular and asks them (mistaking the slug for Phos) to be more friendly to others. At night, Phos sometimes plays card games with other Gems. During one of these games, Phos and Morganite nicknamed Diamond and Euclase "team eyebrows".

Later, the Gems see the changes in Phos' body and personality and begin to respect them as an equal rather than a younger troublemaker sibling. The abilities of Phos' golden arms becomes a novelty to the Gems who played around with it when they first saw it. After Phos successfully infiltrated the Moon and returned, they became even more of a fascination to the other Gems. A number of Gems became thrilled by Phos' stories of the Moon, though there were also some Gems who were suspicious as they noticed that Phosphophyllite became more manipulative. Though some gems want them to go back to their happy, carefree selves. As of Chapter 77, the earth gems have completely turned against Phos and sees them as an enemy despite Phos coming to negotiate with them. The moon gems also seem to have lost care for Phos as they immediately start joking about Cairngorm having more time with the prince after they found out about Phos' demise


Diamond seems to be fond of Phos, and because of that, spoils them more than the other Gems do. Dia was the only one who was concerned when everyone believed Phos was a slug. They also volunteered to persuade Sensei when Phos's plea to go to the ocean was rejected. They didn't get angry when Phos asked to be Bort's partner and was very understanding about the whole situation. Phos looks up to Dia highly, seeming to be their preferable Diamond. They recognize that Dia and Bort's relation is bad and has a negative effect on Dia. Dia ends up joining Phos to the Moon, where their relationship begins to distance. This culminates to the point where Phos threatens to return back to the Moon with Bort in order to get Dia to comply.


Cinnabar claims that Phos is useless and a disappointment, but quietly hopes for Phos to fulfill their one-sided promise. Phos themselves is quite fond of Cinnabar due to Cinnabar accidentally revealing their secret to them. Phos, because they have never been depended upon before, is all the more determined to help them. Phos views Cinnabar as a physically strong and intelligent Gem. They often go to Cinnabar to ask for advice on what their next course of action should be, and Cinnabar often replies with a thoughtful answer. In Chapter 78, Cinnabar was the one to suggest burying Phos' parts to prevent them from being conscious, showing that their relationship with Phos has largely diminished. Cinnabar appears to think of Phos now in a villainous way now.


Bort bluntly called Phos "scraps", thinks Phos is useless and threatens to reduce them to dust. It is not known if Bort was joking or not. After Phos becomes more powerful, Bort asks them to be their teammate. Phos later sees Bort's decisiveness and knowledge in battle as useful and recommends Sensei to make each Gem partner with Bort at least once. Phos sees Bort's criticism of their partner's fighting style as a way of caring. Bort's dislike for Phos in recent chapters is shown by how they cut Phos in half twice. They bluntly state how they believe Phos is a coward and traitor. They do not hesitate to attack Phos.

Yellow Diamond

Yellow Diamond is kind and helpful to Phos but declines being their teammate, claiming to be too old to handle the youngest Gem.


The twin Amethysts are also kind to them, but enjoy teasing them. When Phos kneels and asks them for forgiveness, they both apologize instead, reasoning that they wanted to show off to Phos and let their guard down. Eventually the two are separated, though their relationship with Phos doesn't seem to change despite Phos being the reason they separate.


Alexandrite thought the initial Phos always exaggerated everything. As Phos matures, Alexandrite has a more business like or ally approach to Phos rather than anything friendship like.


Though they are not particularly close to each other, Phos meets Rutile quite often after the doctor takes interest in their rapid physical changes. Rutile is always willing to explain many things to them, and even worries about Phos's disappearance. Rutile overhears Phos's and Padparadscha's discussion, but Phos denies any confrontation to keep Rutile from getting hurt. Phos still remembers Padparadscha as a cool gem and admires them. Phos follows their advice to be more discreet about the truth. Rutile develops a strong hate for Phos after they steal Padparadscha and when they see each other again in Chapter 81, they try crushing shattered Phos into powder until Padparadscha's intervention.


Phos still remembers Padparadscha as a cool gem and admires them. Phos follows their advice to be more discreet about the truth. As of Chapter 81, Padparadscha seems to be one of the only gems to still care about Phos' well being enough to come for them.


During winter, Phos becomes Antarcticite's junior at work. Antarc tells them bluntly about how they do nothing, but after hearing Phos's story and desire to work more, they agree to partner with Phos and teach them how to take care of winter, among other things. Phos thinks of Antarc as a kind and brave person. Antarc's abduction by the Lunarians shocked them so much they started to have hallucinations about them, and took the blame for Antarc's death.


Ventricosus claims that Phos's color looked tasty, hence why she ate them. Phos wants the Gems and Admirabilis to be on friendly terms, but this idea is tossed as it's revealed she was using them as a trading tool in exchange for her brother Aculeatus. Phos accepts this and forgives her, leading her to take compassion and return them to shore.


Perhaps the most complicated of Phos' relationships is theirs with Kongo. At the start of the series, they were very close to Sensei, loving to hide under Kongo-sensei's robe prior to their change, inviting him to card games, and even talking back. Shortly after gaining their new legs, Phos outright admitted to him without any hesitation that they loved him, which is why they were always so eager to fight (something which caught him off guard). Later on, Sensei, in turn admits, that he loves all of the gems as well. As the series progresses, Phos begins to suspect that Sensei knows more about the Lunarians than he is letting on after the encounter with Shiro the dog. This leads Phos to suspect him of being on the Lunarian's side, even going so far as to not rescuing Ghost to see how Sensei banishes Lunarians. After suspecting that Lunarians can talk and forming a plan to go to the moon, Phos discovers from Prince Aechmea that Sensei is a machine created by humans to pray for the Lunarians, and is convinced Sensei is a broken machine that needs to do its job and banish the Lunarians so they won't abduct gems anymore. In an attempt to get him to pray, Phos manipulates several other gems to go to the moon for a second time and betray Sensei.

Upon learning that Antarcticite could not be restored, Phos experienced a moment of further mental instability, where they expressed malice towards Kongo, suggesting that they destroy him rather than make him pray. It is evident at this point that Phos strongly dislikes Sensei, seemingly bordering on hatred. Despite this, Sensei secretly repairs Phos after the gems tear them apart. Phos, after being torn apart and being isolated for more than a century, begs Sensei to pray, not for the Lunarians, but for them, and end their suffering. Kongo momentarily does, but stops suddenly, telling Phos he can't. Phos then snaps and forces Kongo to pray, calling him a machine, and expresses their rage towards him saying "If only you weren't here...".

After being thwarted by the Earth Gems, and being returned to the moon after rescued by Goshenite and Cicada, Phos briefly reflects on the recent events, and realizes that Kongo still cares about them despite everything they have done. They are then incredibly driven and volatile in order to use the caring nature of Kongo to "break" him in order to pray, manipulating some of the other Moon Gems to destroy the Earth Gems.

Gem Info

  • Mineral: Phosphate
  • Chemistry: Zn2Fe(PO4)2•4H2O
  • Color: Blue-green to colorless

Phosphophyllite is a rare mineral composed of hydrated zinc phosphate. Its name derives from its chemical composition (phosphate) and the Greek word for "leaf", phyllon, a reference to its cleavage (the way in which it tends to split or cut). It is highly prized by collectors for its rarity and for its delicate bluish green color.

Phosphophyllite is rarely cut because it is fragile and brittle, and large crystals are too valuable to be broken up.


  • "No way! I want something cooler." - Phos in regards to their job compiling an encyclopedia.
  • "Just don't say you're going to the moon, okay?!" - Phos, to Cinnabar.
  • "The moon is.. where you will start to waver." - Phos, to the other Gems
  • "To the Lunarians, I look like a gem, and, to them, I look like a Lunarian... What am I?" - Phos, to themself
  • "Let's go shatter sensei into pieces! Right now! I don't want sensei to be lonely." - Phos, to the Moon Gems
  • "The past me... so stupid, so pathetic, so foolish..." - Phos, to themself
  • "Grant me mercy. I cannot... find the will to go on." - Phos, to Sensei
  • "If only you weren't here...!" - Phos, to Sensei
  • "Once I crush all gems into dust, I can be free." - Phos, to Aechmea


  • Phosphophyllite is mentioned to have a strong connection with their own inclusions, which allow their memories and personality to be kept more intact even if they lose pieces of themself.
  • Since Gems are mostly inorganic matter, change isn't something that normally happens to them, but Phosphophyllite has undergone many physical changes throughout the story, so much so that more than half of their original body has been replaced by new parts. The series toys with the idea of a Ship of Theseus, a philosophical thought experiment that asks whether an object is still the same if parts of it are placed bit by bit until eventually none of the original parts remain.
  • Ironically, in the beginning, it was suggested by Diamond that Phos change themself to improve, though Diamond meant this more in a behavioural way. But it became more physical as well.
  • From chapter 21 onwards, the agate pattern on their legs was masked by the powder because Phos wanted to stand out less. The agate also displays patterns similar to fire agate.
  • Many of the pieces Phosphophyllite has lost coincide with the idea of the Seven Treasures of Buddhism. As it currently stands, the only piece Phos does not yet have is "carnelian".
  • The collaboration with TASAKI features a Phosphophyllite necklace that has 18K white gold, a South Sea pearl on the left, and a teardrop-shaped phosphophyllite gem on the right.
  • At some point, Phos had arms made of gold-platinum alloy attached to their body to replace their lost arms. Since it was too heavy for their brittle body to lift, the alloy spread and wrapped around Phos' body like a net or lattice, strengthening it. This may be a reference to Kintsugi, the Japanese technique of repairing broken pottery with lacquer that has been mixed with gold, silver, or platinum. This technique is used to embrace the flaws of the broken object rather than disguising it.
  • Their nickname, Phos, is the name for a genus of sea snails.
  • Their change in behaviour after losing Antarcticite appears to be similar to the symptoms of Post Traumatic Stress Disorder, in which the person can develop insomnia, flashbacks, low mood, self destructive behaviour, and occasional aggressiveness. It's possible that each of the Gems suffer from a varying degree of it due to constantly being under the threat of attack and loss. However, a professional diagnosis is needed and the fact that Gems are not good at treating mental health issues is possibly making it worse.
    • Their continuous low mood, guilt-ridden and self-harming behaviour, and being unable to gain much joy in life following Antarc's are also among the numerous symptoms found in depression, although these symptoms could relate to grief also.


KongoPhosphophylliteMorganiteGosheniteRutileRed BerylBenitoiteCinnabarJadeDiamondBortEuclaseNeptuniteYellow DiamondZirconObsidianAmethyst 84Amethyst 33AlexandriteAntarcticitePadparadschaGhost QuartzCairngormWatermelon TourmalineSpheneHemimorphitePeridot • Unknown 28th Gem/s
Morganite (New)Goshenite (New)
HeliodorGreen DiamondRubySapphirePink TopazPink FluoriteLapis LazuliTopazChrysoberylBlue ZoisiteAquamarineApophylliteRed DiamondFluoriteSphalerite