List of fictional elements, materials, isotopes and subatomic particles

This list contains fictional chemical elements, materials, isotopes or subatomic particles that either a) play a major role in a notable work of fiction, b) are common to several unrelated works, or c) are discussed in detail by independent sources.

Fictional elements and materials

Name	Source	Notes
Adamant / Adamantine	Greek mythology	Adamant has long meant any impenetrably or unyieldingly hard substance and, formerly, a legendary stone or mineral of impenetrable hardness and many other properties, often identified with diamond or lodestone. The English word is both a noun and an adjective; from Latin adamans 'impregnable, diamondlike hardness; very firm/resolute position', from Greek adamastos 'untameable'. Adamant or adamantine occur in many works. In myth, Kronos uses an adamantine sickle to castrate his father Uranus; in Prometheus Bound, Prometheus is bound to rocks "in adamantine bonds infrangible"; in Virgil's Aeneid, columns of solid adamantine protect the gates of Tartarus; in Paradise Lost, adamant and adamantine are mentioned eight times to describe the gates of hell, Satan's shield, fallen angel's armor and Satan's chains. In fiction, Adamant is referred to in the film Forbidden Planet, many books and many games. The word adamant is the basis for fictional materials such as Adamantium and Adamantite, Adamantle in The Sims, and Adiamante in L. E. Modesitt Jr.'s 1996 novel of the same name.
Adamantium	Marvel Comics	Adamantium is a nigh-indestructible metal that was inadvertently invented by metallurgist Myron MacLain during an attempt to recreate his prior discovery, an alloy of steel and vibranium. Adamantium is used in Wolverine and Lady Deathstrike's claws, Ultron's shell, Bullseye's spine, and some versions of Captain America's shield. Adamantium also appears in the Games Workshop universe of Warhammer 40000 and the MMORPG Maplestory.
Administratium	Scientific in-joke	First referenced in a 1989 issue of The Physics Teacher. It was apparently discovered by the fictional Thomas Kyle, who was awarded an Ig Nobel Prize for physics for his discovery, and it is a parody on bureaucracy of scientific establishments and on descriptions of newly discovered chemical elements.
Aether	Classical	A classical element referred to as the Fifth Element in ancient and medieval times. It is believed to be the material that fills the region of the universe beyond the terrestrial sphere. This belief goes as far back as Plato's Timaeus, where it is said that "there is the most translucent kind which is called by the name of aether ". In Greek Mythology, Aether serves as a counterpart to mortal air that the gods breathed and also serves as a primordial being serving as the personification of the upper sky.
Aether	Magic: The Gathering	Aether is the main type of energy filling the Blind Eternities, the space between planes in the Magic: The Gathering multiverse, though it can also appear in variable quantities within the planes. Inextricably associated with magic in Magic's shared fictional universe and the use of the word in several Magic cards implies that casting magic involves channeling and manipulating Aether. "Summoning" the creatures around which combat and much of gameplay in Magic revolves is described as "pulling from the Aether".
Bombastium	Disney	Originally appearing in Uncle Scrooge #17 by Carl Barks, Bombastium is stated to be the world's rarest element. Very coveted, but its potential use is not fully known. It tastes different every time one tries it. Scientists find that one atom of it dropped into a barrel of water becomes one barrel of ice cream; a different flavor of ice cream each time. To avoid evaporation, bombastium must be kept frozen. When the element is discovered, Scrooge McDuck tries to secure the entire supply – a ball of "Bombastium" about the size of a large turnip. Terrified that his acquisition will melt before he can make a profit, Scrooge drags Donald Duck and his nephews on a voyage to the South Pole to safeguard his investment, but he has not reckoned on the ruthless determination of the Brutopian agents he outbid to achieve it. Bombastium represents a play on words that negotiates Cold War hysteria about the arms race and the threat of Armageddon due to the H-bomb. Barks' tale is also grounded in fears. The substance is later used in the DuckTales series.
Byzanium	Raise the Titanic!	Fictional element in the book Raise the Titanic! and its film adaptation, which is a main focus of the story arc. It is a powerful radioactive material sought by both the Americans and Russians for use as either an energy source for a missile defense system or an atomic superbomb. The largest known natural source of Byzanium was on the island of Novaya Zemlya, which was mined in the early 20th century and supposedly taken aboard the Titanic during its first and only voyage.
Cavorite	The First Men in the Moon	In the H.G. Wells novel, a metal created by the physicist Cavor that blocks gravity. Cavor builds a spacecraft out of cavorite, by opening and closing shutters the craft can be steered away or towards different heavenly bodies, somewhat analogous to a "tacking" behavior of a sailed ship.
Chelonium	Discworld	According to the wizards at the Unseen University, the species Chelys galactica, including Great A'Tuin, are largely made of this element. Its properties are apparently known to them.
Cobalt Thorium G	Dr. Strangelove, Big Guy and Rusty the Boy Robot	In Strangelove, an element used in the Russian doomsday device. Both elements cobalt and thorium can be used in nukes to increase fallout, which agrees with the sense in which "Cobalt Thorium G" is used in the movie. In the "Wages of Fire" episode of Big Guy and Rusty the Boy Robot, it is revealed that the BGY-11 is powered by a Cobalt Thorium G power core.
Dalekanium	Doctor Who	A polycarbide material from the Daleks' homeworld of Skaro. Dalekanium is a powerful but unstable explosive that is used in the Daleks' body casings.
Dilithium	Star Trek	Dilithium exists ; but something else is referred to in fiction. In Star Trek, dilithium occurs in crystal form and serves as a controlling agent in the matter-antimatter reaction cores used to power the faster-than-light warp drive. In the original series, dilithium crystals are rare and cannot be replicated, making the search for them a recurring plot element. When the crystals appear in the original series they look much like petalite, an important ore of lithium. The name dilithium has led to speculation on whether it is meant as an isotope of lithium or a compound with two lithium atoms. But in a periodic table in a Next Generation episode, it is shown as an element with chemical symbol Dt and atomic number 87, which is in reality francium. Star Trek: The Next Generation Technical Manual gives a chemical formula made of real and fictional elements, instead of treating dilithium as its own element.
Duranium	Star Trek	The fictional metal duranium is referred to in many episodes of Star Trek as extremely hard alloys used in starship hulls and hand-held tools.
Energon	Transformers	A substance or form of energy serving as the primary fuel source for the Cybertronian/transformer race. It often takes the form of a liquid, most often as "energon cubes" refined from other sources of chemical energy.
Fraudulin	Monty Python's Flying Circus	First used in 1970 in the "Crelm Toothpaste" sketch of the season 2 episode "How Not To Be Seen", and again in 1971 when the same sketch was re-released as part of the Pythons' film And Now for Something Completely Different. A chemical of obscure composition, ostensibly a powerful preventative of tooth decay and invariably referred to as "the miracle ingredient, fraudulin", it is a parody of the use of questionably effective "miracle additives" in advertising puffery.
Gaulau	Glinda of Oz	In L. Frank Baum's last Oz book, published in 1920, Glinda says that the magical "rare mineral powder called gaulau" is "more wonderful even than radium". The text describes it as "a grayish powder, the tiny grains of which constantly moved as if impelled by some living force". When a magician burns a small amount of gaulau, its magical activity, directed by the correct spoken words or incantations, is capable of powering magical heavy machinery, including an expanding steel column which lifts an entire underwater village from the bottom of a large lake to the surface, and holds it at the surface indefinitely, until more gaulau is used to submerge the village again.
Harbenite	Tarzan at the Earth's Core	Appears in Edgar Rice Burroughs' novel Tarzan at the Earth's Core. Harbenite, named after its discoverer, Dr. von Harben, is a metal found in the fictional African country Urambi and is described as lighter than cork and stronger than steel. Harbenite was used to build the O-220, a dirigible airship built for a rescue mission to the Earth's core in response to a radio distress call from David Innes and Abner Perry, the original discoverers of the inner world of Pellucidar in the novel At the Earth's Core.
Inertron	DC Comics	The densest substance in the universe. The walls of the Legion Clubhouse are composed of an inertron alloy.
Jerktonium	It's a SpongeBob Christmas!	A green superheavy element. Ingestion of jerktonium causes a bad attitude, but the effects are curable by song. Other side effects of ingesting this element include a fast growth of stubble, a look of fatigue radiated by bags under the eyelids, and thick eyebrows.
Jumbonium	Futurama	Very rare and valuable element with atoms big enough to be seen by naked eye. In the episode "The Lesser of Two Evils", a Jumbonium atom is used in 3001 for the Miss Universe competition, where it hovers above the prized tiara. According to Bob Barker, the atom is worth $200,000 or, at least, somewhere between $200,000 and $200,001. Professor Farnsworth says the nucleus alone is worth $150,000.
Katchin	Dragon Ball Z	Said to be the hardest material in the Dragon Ball universe. When testing the Z Sword, Goku throws a cube of Katchin, which was summoned by Supreme Kai, at Son Gohan in order to test the sword's supposed legendary strength. The block of Katchin proceeds to snap the Z Sword when Gohan tries to slice it.
Kryptonite	DC Comics	A crystal originating from the planet Krypton that became radioactive when the planet exploded. The radiation is harmful to Kryptonians. Kryptonite comes in various colors with differing effects, and has been variously depicted as an element and compound. Green Kryptonite is fatal to Kryptonians.
Kyber crystal	Star Wars	A rare, semi-sentient, crystalline material found across the galaxy. Kyber crystals vary in shape and color, but all are deeply connected to the Force, the vast energy field connecting all living things. They are most commonly used by the Jedi and Sith in making lightsabers; but larger, rarer crystals are sometimes used in superweapons, including the planet destroying Death Star.
Lerasium	Mistborn	A metal forming the body and power of the shard Preservation that makes any non-allomancer who ingests it an extremely powerful mistborn. All known samples are destroyed after the last was ingested by Elend Venture. It is the source of the Lord Ruler's and the first noble's Allomantic abilities, being found by Rashek at the well of ascension. Its Allomantic, Feruchemic and Hemalurgic powers are unknown. It is named after the holder of Preservation, Leras.
Lunarium	Radar Men from the Moon	"More powerful than uranium"; used by men from the Moon.
Meteorillium	Return to Castle Wolfenstein	Element found in meteors theorized to originate in the center of the galaxy. The Schutzstaffel's Special Projects Division discovers some of the rare element in the Baltic states. Oberführer Strasse's project book indicates that the SS Paranormal Division needs it for the resurrection of King Henry the Fowler. Strasse's lab in Norway refines the metal into its 317 isotope for use in the ceremony.
Mithril / Mythril	Various	Originally from Tolkien's The Lord of the Rings. A durable silvery metal; very light and extremely strong. Mithril means "grey gleam", but is translated as "true silver". It is mined in native form in Moria. It can also be worked into other forms with unusual properties such as reflecting only the light of the Moon. The fictional metal has appeared in other fantasy universes, games, and books. "Mythril" appears in the video game series Final Fantasy and Kingdom Hearts. "Mithral" is used in D&D books; "Milrith" in Simon the Sorcerer. In Warhammer, the High Elven metal "Ithilmar" has similar properties and use. In RuneScape it is a lightweight blue metal stronger than steel. In World of Warcraft, mithril and truesilver both appear; truesilver is a rare spawn node in the same areas as mithril. Both can be mined as ore and smelted into a bar using the mining profession. Mithril also appears in the MMORPG Guild Wars 2 as a blueish-silver metal used in crafting. In Defense of the Ancients, the multiplayer online battle arena version of Warcraft, players can buy the Mithril Hammer from the Main Shop. "Mithral" also features in the Dungeon Master series. It appears in armor form in The Elder Scrolls IV: Oblivion. It appears as a cyan metal used to make armor and weapons in MapleStory. Mythril is also depicted as a teal-color metal used to craft armor, weapons, and tools in Terraria.
Moustachium	Team Fortress 2	Yellow metal bars given to people who gained achievements in the game SpaceChem. It can be used to craft items such as fishcake or a SpaceChem pin.
Mysterium	Marvel Comics	Platinum silvery in appearance, Mysterium is a meta-material created when loosely formed Kirbons are condensed into singular, varied shapes. The metal has energy-conductive properties and is easily twice as resilient as Adamantium. It is also anti-magical, which makes it useful as a weapon against Arcanum.
Nanite	I Expect You To Die	Yellow liquid with atomic number 13 and symbol Nn; makes a compound that explodes when exposed to air when mixed with Galine, and an antivirus when mixed with Regalite and Sanite. The real element 13 is aluminium.
Naquadah	Stargate	First depicted as a quartzite-like "mineral" in the original Stargate movie. Naquadah is an extremely dense metallic transuranic element in the island of stability, and is superconducting at room temperature. Rare and valuable, and not occurring naturally in the Solar System, its peculiar properties led to its use as the basis for many advanced technologies, including the Stargates themselves, of which naquadah is the primary constituent. Naquadah greatly amplifies energy, making it extremely potent if paired with explosives. It also occurs in the bloodstream of the Goa'uld, which allows them to control their technology and sense the presence of other symbiotes. The Goa'uld have naquadah mining operations on many planets, and make use of refined naquadah as a form of currency. Naqadah is used in liquid form, to power Goa'uld staff weapons, and heavy liquid naquadah is used to power Goa'uld AG-3 weapon satellites. Naquadah can also be used to create weapons of mass destruction.
Naquadria	Stargate	This heavy, unstable isotope of naqahdah is 100 times more powerful, highly radioactive, and does not occur in nature. A very large artificial vein was discovered and mined on Kelowna for use in weapons of mass destruction. It was also used by Stargate Command to power the hyperspace generators on the prototype X-302 and X-303 spacecraft.
Netheranium	Marvel Comics	A psycho-sensitive metal originating from Satan's extradimensional plane. Daimon Hellstrom's trident is made of Netheranium, which enables him to fly and manipulate mystical energy.
Netherite	Minecraft	A powerful metal, first refined from blocks of "ancient debris" in the Hell-like Nether dimension to obtain netherite scraps, which can then be alloyed with gold to create a usable ingot form. Coating diamond weapons and equipment with the ingot form creates netherite equipment, the most powerful material tier in the game, increasing their durability and preventing them from being destroyed in lava.
Nth Metal	DC Comics	A Thanagarian alloy used by Hawkman and Hawkwoman. It can negate gravity and magic, among other properties. In some versions, the Legion of Super-Heroes' flight rings are made of valorium, an alloy containing Nth metal.
Octiron	Discworld	A strange, iridescent metal; highly valued. It radiates dangerous amounts of raw enchantment and is so unstable it can only exist in a universe saturated with raw magic.
Orichalcum	Mythology of Atlantis	Pink or red metal mined in Atlantis; also called mountain copper. May be based on Auricupride. Powers machinery in Atlantis in the video game Indiana Jones and the Fate of Atlantis. In Exalted, Orichalcum is the strongest of the five magical materials and can be made by distilling ordinary gold using Gaia's blood and concentrating sunlight using large occult mirrors. Found in Final Fantasy as a rare material with varying properties. In the Soul Calibur series, Sophitia carries a sword and shield set named Orichalcum. A green metal used in smithing to craft Orcish weapons and armor in The Elder Scrolls V: Skyrim. In Maplestory it is a fuchsia metal used to craft armors and items. In Guild Wars 2, Orichalcum appears as an amber-colored metal used in crafting various things. In Shadowrun, orichalcum is a magical alloy of gold, silver, mercury, and copper. Also named "Orichalcon" in some games. Orichalcum is depicted as a pink metal in Terraria and is used to make weapons, armor, and different walls and blocks. It also appears in Harvest Moon as a resource in multiple entries in the series. In the online game Forge of Empires, it is a golden-brown "special good" which can only be mined undersea during the Oceanic Future and later eras. Also mentioned in the "Biggles" story "The Adventure of the Oxidized Grotto" from Biggles - Charter Pilot.
Phostlite	Tintin: The Shooting Star	Extraterrestrial mineral found in a meteorite that lands in the Arctic Ocean. Phostlite accelerates growth and increases size, causing gigantic apple trees to grow from a single apple core and causing insects and spiders to grow to enormous sizes.
Polydenum	OtherSpace	A metallic, radioactive, explosive element found in some planetary cores that is mined and refined to become the main fuel for starship sub-light engines in the OtherSpace multiverse, and a potent explosive.
Polydichloric euthimal	Outland	Powerful amphetamine. Greatly increases miners' productivity in the British sci-fi thriller Outland. Prolonged use leads to severe psychosis often ending in deadly violence or suicide. In the 1991 American sci-fi action film Terminator 2: Judgment Day, the barrels of explosive used to destroy the Cyberdyne building are labeled "Polydichloric Euthimol" as an in-joke.
Protodermis	Bionicle	Artificial substance. Comprises all of the giant robot Mata Nui and the beings that live inside it. Liquid protodermis functions similar to water; solid protodermis can function as earth, stone, or metal. Organic protodermis forms the biological components of the characters. A naturally occurring form, Energized Protodermis, is a silver-colored liquid that is a sapient being, and can transform or destroy any living thing that touches it.
Protomolecule	The Expanse	An unusual, exotic substance discovered in Saturn's moon Phoebe by the corporation Protogen. When introduced to living tissue, the protomolecule undergoes strange processes, seeming to deconstruct the life in order to turn it into new structures. With a larger sample of biomass, the complexity of the protomolecule's processes seems to increase, and becomes able to do things that appear to violate the laws of physics, such as accelerating and decelerating objects in defiance of Newton's third law. Ultimately, it is revealed that the protomolecule was a form of self-replicating spacecraft created by a powerful alien civilization billions of years ago, with the goal of assimilating enough biomass to allow the protomolecule to become a massive ring structure that can be used as a wormhole.
Pyrholidon	Disco Elysium	A radiation sickness treatment with psychedelic side-effects. Pyrholidon has the same chemical structure as the real drug AEOL-10150. AEOL-10150 is a drug in development designed to treat sulfur mustard and nerve agent exposure, as well as pneumonitis due to acute radiation syndrome. Pyrholidon's in-game description is as follows: "A pretty little puck-shaped cap of purple liquid that can bring on anything from hot flashes to military-grade psychosis. With sufficient tolerance, however, it can make any weather feel balmy – if only for a while."
Quantonium	Monsters vs. Aliens	A blue-green luminescent material that is used as fuel. When the protagonist, Susan Murphy, is hit by an asteroid filled with quantonium, she grows to a gigantic size.
Radianite	Valorant	Grey crystal-like substance. Has become a major part of Earth's civilization after its discovery. Is used to power and augment much of Earth's technology and is the game's main plot device; one team has to steal large amount of crates containing radianite, while the other team has to defend objectives to keep the opposing team from stealing the crates. It was initially known to be a clean, safe source of energy and something that could inflict supernatural abilities upon certain people who come into contact with it. Known as Radiants, they made up only a relatively small section of the global population and eventually became an accepted part of society. After a disaster in Venice, it is revealed that radianite had more destructive potential, leaving the world questioning how safe radianite actually was.
Radium X	The Invisible Ray	Highly radioactive extraterrestrial element discovered by Dr. Janos Rukh. He uses it to create a death beam projector which uses the incredible power of Radium X for a destructive weapon of mass terror. After developing a filter to curb its destructiveness, Rukh also uses it to restore sight to his blind mother with the Radium X projector. According to legend, this scene inspired John H. Lawrence to use radiation on his mother, who had been diagnosed with inoperable uterine cancer.
Raysium	The Stormlight Archive	Bright golden metal forming the body and power of the shard Odium that conducts investiture, drawing it in from any source. Used by the forces of Odium to drain Radiants of their stormlight and to transfer spren between gemstones.
Rearden Metal	Atlas Shrugged	Greenish-blue alloy containing iron and copper invented by Hank Rearden. Lighter and stronger than traditional steel, it is to steel what steel was to iron.
Rebellium	Space: 1999	Rebellium appears on a computer monitor during Episode 24, Series 2, The Dorcons in which Moonbase Alpha is attacked by The Dorcons who are attempting to kidnap Maya who is a Psychon. Rebellium is one of the constituent elements of the Dorcons space craft.
Red mercury	Urban legend	Hoax substance of uncertain composition purportedly used in making nuclear bombs. It appears in the films Red Mercury and Red 2.
Redstone	Minecraft	A naturally-occurring substance capable of generating and conducting energy similar to electronic circuitry. The player can mine it in a powder form from ore deep underground and use it to build complex logic gate systems or automated resource farms.
Regalite	I Expect You To Die	Purple liquid with atomic number 11 and symbol Re that makes a compound that produces clouds when exposed to air when mixed with Arsonium, and an antivirus when mixed with Nanite and Sanite. The real element 11 is sodium; and Re = rhenium.
Residuum	Critical Role, The Legend of Vox Machina, The Mighty Nein	A mineral; can enhance arcane powers. Refined from whitestone rocks. During Exandria's Calamity, a fight between the gods created mountains infused with their magic; whitestone is mined from these mountains. Residuum can be further refined into suude – a performance-enhancing drug which improves spellcasting. It first appeared in campaign one of the Dungeons & Dragons web series Critical Role; it later appeared in other Critical Role campaigns and the animated adaptations. Mechanically in the D&D game, residuum can replace expensive components consumed by spells and other arcane rituals.
SAM	Satisfactory	Glassy purple/indigo mineral able to manipulate atomic bonds of any matter within physical contact of it when "Reanimated". Used to transform materials, and to progress through alien technology research.
Sanite	I Expect You To Die	Red liquid with atomic number 17 and the symbol Y. Makes a compound that is corrosive to copper when mixed with Arsonium and Galine, and an antivirus when mixed with Regalite and Nanite. The real element 17 is chlorine and the element with symbol Y is yttrium.
Saronite	World of Warcraft	Teal-color metal found in the land of Northrend. Said to be created from the blood of the old god Yogg-Saron. Those who spend a long time in Saronite mines will complain of ghostly whispers and be driven to insanity. This metal is also used by the Scourge and Knights of the Ebon Blade to create armor, though the creators of the game confirmed that using Saronite in armor will not affect the wearer. In the game, Saronite can be used by blacksmiths and engineers to craft rare and epic-quality armor and weapons.
SCP-148	SCP Foundation	Alloy: mainly platinum and iridium, plus several other known metals and unidentified matter. SCP-148 has a passive effect that negates extrasensory perception. Long exposure causes communication disorders; extensive overexposure leads to complete aphasia with no visible signs of brain damage.
Scrith	Ringworld	Structural material for Ringworld, with tensile strength on the order of the strong nuclear force.
Seastone	One Piece	A rare substance that "gives off a wavelength that is the same as the sea itself", making it, in effect, a solid form of sea. Any person with superhuman powers obtained from a Devil Fruit has said powers temporarily neutralized if they come into contact with Seastone.
Septium	Trails	Septium are gemstones that align with one of seven elements: Earth, Fire, Water, Wind, Space, Mirage, and Time. Septium is central to the function of Orbal energy, which can power appliances, vehicles, or channel elemental power in the form of "Arts", magical techniques used in combat.
Silver rock stone	Pokémon	A silvery substance, one of the hardest in the Pokémon world, and which only occurs on Silver Rock Isle. The locals sell wing-shaped pin talismans fashioned from silver rock stone.
Silverstone	Elemental Assassin	Magic metal that can absorb and negate elemental magic, at the cost of generating heat. This ability lets Silverstone be used for both storing magical energy to be used later and to protect people, objects, or structures from mystical attacks. Silverstone is also durable against mundane force, with shooters preferring it to Teflon for armor-piercing bullets.
Solaronite	Plan 9 from Outer Space	A substance that explodes sunlight particles. Such an explosion would set off an uncontrollable chain reaction, destroying the universe. This is what the antagonists of the movie seek in their plot to destroy Earth and humanity.
Space Titanium	Godzilla vs. Mechagodzilla	Also called "space metal". Strong metal from outer space used by the Black Hole Planet 3 Aliens to create Mechagodzilla. After Godzilla destroys Mechagodzilla, the Black Hole Planet 3 Aliens use this metal to create a second Mechagodzilla in the 1975 sequel Terror of Mechagodzilla.
Thiotimoline	Isaac Asimov	Fictional chemical compound. Its major peculiarity is its "endochronicity": it starts dissolving before it makes contact with water.
Thirium	Detroit: Become Human	Primarily used for the synthesis of "Blue Blood", a fluid that circulates energy and information inside CyberLife androids. It has a destabilizing effect on hormone production.
Tiberium	Command & Conquer	An extraterrestrial crystalline structure, it grows and spreads like a living organism. The green crystals are made of various minerals such as phosphor and iron and 1.5% of unknown matter. When refined, it can function as a high energy fuel and be turned into both a weapon and building materials with relative ease. It causes various health issues and Tiberium poisoning to anyone in contact with it. Named after the Tiber River where it was first found in 1995.
Timonium	Numerous works	In the Liaden universe, the planet Surebleak was once a mining center for timonium before large amounts were discovered in another nearby star system. Timonium is a radioactive element used as an internal power source for high tech devices. The material has also been featured in The Stardust Voyages, and in Rise of Nations: Rise of Legends.
Transformium	Transformers: Age of Extinction	A programmable material that the Transformers are made from.
Tritanium	Star Trek	The fictional metal tritanium was referred to in many episodes as an extremely hard alloy used in starship hulls and hand-held tools.
Tritanium	Eve Online	A versatile material; the primary material used in the construction of virtually all star ships and star ship components. It is described as being unstable at atmospheric temperatures, and thus is only used in constructing objects intended to stay in space permanently.
Trellium	Wax and Wayne	Trellium is a silvery red god metal with dark red spots similar to rust. It is the solid form of the Shard Autonomy's power. It is around a 9 on the Mohs Hardness Scale and repels Investiture. Unlike most other god metals in the Cosmere it is not commonly known by name of the vessel of the Shard from which it originates which would make it Bavadinium. Due to its ability to repel Investiture it is used along with Harmonium to create Weapons of Mass Destruction comparable to Thermonuclear weapons. These weapons of mass destruction create Atium and Lerasium as a by-product of their detonation.
Truthitonium	The Ambidextrous Universe	Martin Gardner describes Truthitonium as the invention of Ralph Cooper of Los Alamos. It is created momentarily, by annihilating a Truthiton with a pseudo electron, after which it degenerates releasing 2000 neutrinos and then implodes into nothingness "leaving behind not a particle of Truth".
Ultron	Armageddon 2419 A.D.	A synthetic material which is an "absolutely invisible and non-reflective solid of great molecular density and moderate elasticity, which has the property of being 100 percent conductive to those pulsations known as light, electricity and heat". In the novel, the Americans use this technology, combined with Inerton, as well as explosive rockets and radio frequencies the enemy cannot detect, in their struggle with the main antagonists, "The Hans".
Unobtainium	Aerospace term	A substance with the exact properties needed for a piece of hardware or other item of use, but not obtainable, either because it theoretically cannot exist, or because geopolitical events preclude access to it, or because current technological limitations prevent making it.
Unobtainium	Avatar	Unobtanium is also the mineral being sought on Pandora by brute-force mining methods in the film Avatar. It is a room-temperature superconductor.
Unobtainium	The Core	A material invented by Dr. Brazzelton, who dubs it "unobtanium" as its technical name has 37 syllables. Unobtanium is able to convert heat and pressure into energy that reinforces its own structure, allowing the construction of a vessel capable of enduring a trip to the Earth's core. In addition, it can also turn heat into electric power. Unobtanium is created by combining unspecified crystals in a tungsten-titanium matrix at low temperatures.
Upsidaisium	The Adventures of Rocky and Bullwinkle and Friends	A focus of the second-longest Rocky and Bullwinkle story arc, Upsidaisium, an anti-gravity metal, is much sought after by the US government. Bullwinkle comes to the attention of government agents, as well as spies Boris and Natasha, after inheriting his uncle's Upsidaisium mine. The mine is located in the fictional Mt. Flatten, which floats high in the air due to the high amount of Upsidaisium within.
Uridium	Uridium	Fictional metal named in the 1986 computer game Uridium, available for the Commodore 64, ZX Spectrum, BBC Micro, and Amstrad CPC. Each level of the game takes place on a space dreadnought named after a different metal. The last level is named after the fictional element uridium. The cassette inlay card says the name was created by one of the game developers who thought uridium really existed.
Uru	Marvel Comics	An extremely durable metal from Asgard that is easily enchanted. Thor and Beta Ray Bill's hammers, Mjolnir and Stormbreaker, are made of Uru.
Valkyrium	Pathway	In the 2019 indie game Pathway by Robotality, a large Valkyrium network is believed to extend from the African Atlantic coast to the Caucasus. Known to the ancient Egyptians as Ka and called Valkyrium-500 by the Germans, these green crystals are of unknown origin and were collected by the Nazis for their Projekt Walhalla to unleash the powers of ancient artifacts.
Versamina		Versamine are substances that turn pain into pleasure.
Verterium cortenide	Star Trek	Has a key role in Star Trek's warp drive propulsion system, since it is described as the only compound able to generate warp fields when given energy from the warp core. The crew of USS Voyager are forced to land on a planet to retrieve verterium cortenide to repair their warp nacelles after a sabotage.
Vibranium	Marvel Comics	Vibranium is a rare metallic substance that is theorized to be of extraterrestrial origin and closely associated with Wakanda. It exists in two forms: the Wakandan variety is found only in Wakanda and can absorb energy. The Antarctic variety, known as Anti-Metal, is found in the Savage Land and can produce disintegrating vibrations.
Vizorium	Dirty Pair: Project Eden	An extremely rare metal that is illegal and sold by various criminals. It is used to power warp drives.
Wapometal	One Piece	An alloy that was inadvertently invented by Wapol when he was turning garbage into toys during his cover story, manufactured via his Munch-Munch Fruit powers. It was this metal that turned him from a homeless bum into a very wealthy CEO of a toy company.
Wishalloy	Aerospace term	Alternative to unobtainium; may mean that said substance is theoretically impossible under known scientific theory. Historically scramjets have been described as being made from unobtainium reinforced wishalloy.
Wonderflonium	Dr. Horrible's Sing-Along Blog	A substance needed by Dr. Horrible to complete his time-stopping Freeze Ray. A case containing the substance has the admonition "Do Not Bounce", although the reason for this isn't explained.
Xirang	Chinese mythology	Magic soil that can self-expand and continually grow. Used to fight against the waters of the Great Flood.
Xirdalium	The Chase of the Golden Meteor	Element which is, in the French first edition of the novel, ~100,000 times more radioactive than radium. In the English first edition this is reduced to 100 times. Xirdalium was invented by Jules Verne's son Michel, who introduced it to the novel, together with the character Zephyrin Xirdal, a 'private genius' who synthesized the new element. In the story Xirdal then uses Xirdalium in a contraption emitting a strong tractor beam able to alter the trajectory of the meteor mentioned in the novel's title.
Xithricite	Vendetta Online	A bright green mineral used to produce incredibly strong alloys originally discovered by explorers from the Neutral Territories. References to it are found throughout the game's item descriptions. Is used in everything from spaceship hulls to railgun ammunition. Players can mine Xithricite ore from asteroids.
X-linked Herculite	Voyage to the Bottom of the Sea	Harriman Nelson's military-classified transparent metal, sold to the US Navy as battleship hull armor. With the billion-dollar profits, Nelson employed the material as the hull his for "USOS Seaview," a nuclear submarine for scientific research.
Z-Crystals	Pokémon	Mysterious crystals to be held by Pokémon and used in battle to upgrade normal moves to Z-Moves. There are 18 Z-Crystals for each type and 17 for specific Pokémon.
Zynothium	Teen Titans	A red compound that is highly unstable, dangerous, and rare. Its properties allow it to act as a power source and it powers the Red X suit.