Remember that old joke about two people deciding which restaurant to go to?
Well, these guys do, apparently.
There's a tendency in fantasy to have certain species or characters eat earthen materials. Often, this extends to having their entire diet consists of these things, and they're unable to digest pure organic matter. Analogies to actual human food may be drawn as well: nitrogen-rich soil may be especially tasty, for instance. Gemstones may be considered rare delicacies, quartz may clog arteries and rust means that it's spoiled.
This is particularly common for creatures themselves made partly or entirely out of rock, but this trait is sometimes also given to dragons, which may be depicted as capable of feeding on gems and metal to provide a motivation for amassing vast hoards of the stuff.
How they get their nutrition from eating such materials is never explained, but, presumably, if they're different enough to find rocks tasty, their nutritional needs are far different from ours.
Truth in Television, surprisingly enough. Referred to as geophagia, in humans it can be a result of pica (an eating disorder) or cultural tradition, and it's anything but uncommon in animals, to say nothing of non-animal organisms.
Not to be confused with Tasty Gold, where someone bites down on a coin (without consuming it) to confirm that it's genuine.
- inFairy Tail: Dragon Slayers can, in addition to normal food, consume the element that makes up their magic to quickly restore their magical power and sometimes as a substitute for normal meals. This trope thus comes into play for Gajeel, the Iron Dragon Slayer, who is often seen eating from a bowl of nuts and bolts during his downtime. It would presumably also apply to any hypothetical Dragon Slayers using other metals or stone or minerals as elements.
- In Monster Rancher Golem eats rocks like food, and consumes sand like a beverage.
- Concrete: Ron Lithgow's alien cyborg body regenerates itself by consuming silicate matter. Fortunately (at least in this case) it has no taste buds, so eating rocks is no big deal.
- Suske en Wiske: the story "De Steensnoepers" resolves around the protagonists discovering a race of intelligent creatures called Toeketoes, who live entirely on rocks. While defending their hidden village from the Big Bad, they hope to find out how their digestive system works in hopes it can be replicated for humans (and thus solve the problem of world hunger), but in the end this proves impossible.
- In Galaxina, the Space Police have an alien prisoner on their cruiser who eats rocks. The Captain amuses himself feeding the prisoner by chucking rocks at its head.
Alien: OW! Is this how you get your rocks off?
- Monty Python and the Holy Grail: Parodied with the Constitutional Peasants, who are seen gathering dirt and filth in the same way one would harvest crops.
- Alluded to by H.I.'s cellmate in Raising Arizona:
- "...when there was no crawdad to be found, we ate sand."
- "You ate sand?"
- "We ate sand."
- Age of Fire: The dragons' metal diet is what makes their scales so strong, and failure to include a steady amount of metal in one's diet is equivalent to vitamin deficiencies. In fact, AuRon is special for averting this, as he is a rare scaleless dragon and so doesn't need to eat any, allowing him to live far from the hominids who mine the stuff.
- Alien in a Small Town: While the silicon-based Jan can't make up their entire diet out of them — they grow silicon-based crops, as well — they're perfectly capable and happy to eat rocks.
- Artemis Fowl: Dwarves are essentially humanoids who evolved to fill the same niche as earthworms, and tunnel by devouring the soil in their way and rapidly, ah, expelling it at the other end after digesting anything useful within it — consequently, their diet is chiefly made up of soil minerals, clay, insects, and the occasional rabbit. Gemstones, diamonds in particular, can cause severe intestinal blockage, so they avoid those.
- The Chronicles of Narnia: The walking trees eat soil and dirt. It even mentions a trees' feast with different courses.
- Discworld: The trolls, which are themselves made entirely out of stone, eat gems and rock, and have teeth made of diamond to facilitate this. And yes, it is possible for them to complain about the food, as CMOT Dibbler discovers in Men at Arms.
First troll: Dis shale is stale.
Second troll: Yeah, and dere's bloody quartz all through dis granite. Clogs the arteries, quartz.
- The Fifth Season has legends of the Stone Eaters, humanoid creatures of living stone that inhabit the continental plate. When they show up in person, it's revealed that the stone they prefer to eat is human flesh that's been Taken for Granite. Later Subverted when their diet turns out to be their means of transforming a human into a Stone Eater.
- The Heroes of Olympus: Arion is an immortal horse that only eats gold.
- Methuselah's Children by Robert A. Heinlein has an incident in "The Crazy Years" mentioned briefly, "Earth-Eating Fad Moves West: Chicago Parson Eats Clay Sandwich In Pulpit. "Back to simpler things", he advises flock."
- The Neverending Story: The Rockchewers are a race that eats nothing but rocks. They don't need to eat often, but they've lived in a certain mountain range for so long that the mountains have some many holes in them that they look like Swiss cheese. They also make pretty much every type of furniture out of them, including, as is the case of the one in the book, a giant bicycle-like vehicle. (Unfortunately, he has a "sudden burst of hunger" on the way to the Childlike Empress' palace and eats it, and has to walk the rest of the way.)
- Perry Rhodan: The inhabitants of Halut, distant descendants of genetically engineered alien Super Soldiers who rebelled against their creators, are technically more Extreme Omnivores, but one of them taking a quick bite out of a convenient piece of rock when nothing else is immediately handy is certainly not an uncommon sight.
- Tortall Universe: Basilisks eat rock, which is why they turn their prey into stone. They regard some types of rock as more edible than others, and certain gemstones qualify as "dessert".
- In Prehistoric Park, much to the annoyance of the park staff, Titanosaurs are able to consume whole trees and thatched huts, but they prefer rocks. Justified in that the rocks allow their digestive system to crush the massive quantities of fibre they consume, easing indigestion; they can't dig except by uprooting trees, so finding an appetizing rock is not as easy as one might expect.
- Ultra Series: A number of kaiju turn out to be lithivorous.
- In the original Ultraman, a Monster of the Week named Goldon eats pretty much what the name suggests it does. In fact, Goldon's body is partially made of gold!
- Pagos from Ultra Q feeds on uranium, giving it atomic abilities. This is also the case with a similar monster named Gabora that appears in Ultraman and Kingsaurus III from Return of Ultraman.
- The Arindo Ants of Ultraman Taro eat steel and concrete like termites eat through wood, causing structures to collapse.
- Gakuma of Ultraman Tiga mainly lives on minerals, but after miners exhaust the resources, it begins to attack living creatures with its petrifying beam for sustenance.
- Ultraman Dyna: The volcano monster Sodom consumes igneous rock underneath volcanos, diverting lava to new tunnels and preventing eruptions. Also, the demon Mozui was fed pebbles by its followers but it didn't gain any sustenance from the rocks, but rather the fear that its worshipers put inside the stones.
- In Ultraman Max, the iconic kaiju Red King is given this trait. He swallows chunks of the explosive sediment that composes his island in order to spit them out as a Breath Weapon.
- Gromite from Ultraman Mebius feeds on mineral matter in order to harden its stony exoskeleton.
- Dungeons & Dragons:
- All metallic dragons like eating some types of gems, and (at least according to the 3.5 Draconomicon) all true dragons can subsist off of stone and earth, although most prefer meat to dirt. Gold dragons, who refuse to harm any living creature, eat nothing but gems and jewels
- Khargra, creatures resembling circular, whirling maws with bodies attached as afterthoughts, tunnel their way through the earth to eat high-grade ores.
- The xorn, and their cousins the xaren, feed on rare minerals. In module S4 The Lost Caverns of Tsojcanth, they eat crystals and gems.
- There is a titanic, worm-like Eldritch Abomination that eats soil and stone Beneath the Earth and whose excreta shatters psyches just by being near it. It's revered by the Aboleths.
- The aurumvorax is an eight-legged wolverine-like animal that eats metals and ores, but has a special affinity for gold.
- According to Spelljammer, this is actually the natural diet of tarrasques on their isolated homeworld. The more familiar all-devouring, all-destroying monsters are all just homicidally insane — most planetary atmospheres don't agree with them.
- Rust monsters subsist on rust, which they can create by touching any kind of metal. Their cousins, the folugubs, can liquefy crystals at a touch and feed on the result. Planescape reveals via retcon that rust monsters are larval forms of a much more dangerous creature called a rust dragon, which is encountered on Acheron. Their breath weapon can rust and corrode an arsenal's worth of armor in one blast. Fortunately, Acheron is full of scrap metal, but rust dragons crave metal from outside sources the way humans enjoy candy. (A rust dragon who finds itself in Mechanus, a plane made entirely out of gigantic metal gears, is a planar bull in a china shop, and is quickly hunted down by the inhabitants.)
- Pathfinder: In addition to creatures such as xorn, aurumvorax and metallic dragons maintaining their mineral-eating habits from D&D, blue dragons are noted to sustain themselves on mineral-rich sand as a last resource, which they strain through their teeth while burrowing beneath the desert when prey is particularly scarce.
- Some kinds of Host Armor can be Lithovorous, which makes them easy to maintain in the field. It also makes the ammunition for any Casting Guns especially hard.
- At least one kind of War Mount, the Tunnel Rat, is lithovorous, too. The fact that they spend a lot of time digging through the earth anyway means they're basically the easiest War Mount to feed every day.
- Warhammer: Stonehorns, gigantic beasts that live in the Mountains of Mourn with horns, facial plates and tusks made out of stone, feed by smashing cliffsides to rubble and consuming the choicest ores and mineral deposits, alongside the piles of scree generated by their foraging and any unfortunate mammals whose burrows they shatter.
- Animal Crossing: In Animal Crossing: Wild World, the player can donate to the poor town of Boondocks, whose residents eat nothing but grilled cheese sandwiches... without bread... or cheese. So they eat grilled dirt.
- Blazing Dragons: The Licensed Game has the title characters eating various gems. Flicker also has to eat a piece of coal to gain his fire breath ability for a moment.
- Copy Kitty: Boki is from a race of cat people that eat crystals. Her favorite is emerald. This information explains why she can claw her way through terrain: in her natural habitat (caves), she would have to be an excellent digger to get at those crystals.
- Crash Fever has the Nian Beasts, who eat Bits and Polygons. Mi-Go also eats Junk, and his enormous appetite causes Starfire Upon The Ice to unfold.
- Don't Starve: Deep within the caves there are the Rock Lobsters. They're basically the pigs of the underground, but you gain their allegiance by feeding them rocks and flint.
- Final Fantasy I had a talking stone giant blocking the path to get to the Earth Cave. He wants a tasty ruby to munch on.
- In Fossil Fighters Frontier, there are Vivosaurs called Fossil Eaters who, well, eat fossils. They're otherwise normal Vivosaurs (normal by Vivosaur standards, anyway), but the fact that they eat fossils means that, in the areas where they appear, you'll have to defeat them before they eat the nearby rare fossils.
- Kantai Collection: By the nature of things, characters are usually depicted as straight-out eating bauxite, which is one of the resources in the game. Especially Akagi, who is depicted as usually devouring your bauxite supplies.
- The Legend of Zelda: Gorons have been mentioned to eat mostly rocks; one Goron describes his race as the "stone-eating people from the mountain." But they don't just eat any rocks. One Goron says they've become such gourmets that other rocks may as well turn to ash in their mouths, for all the satisfaction they get from eating them.
- Later games add some other mineral-based meals for Gorons, usually as a part of sidequests: one game has you delivering a rock sirloin (a hunk of rock that resembles Cartoon Meat) to a stranded Goron while another has you delivering a bowl of lava soup to a sick Biggoron. They also like to eat amber, even if it has fossilized bugs inside it.
- Certain traveling Gorons in Breath of the Wild reveal that ore, gems and the like are unpleasant meals of choice. Amusingly enough, throwing one of those in your cooking pot will give you Rock-Hard Food; it restores one-quarter heart (equivalent to an uncooked acorn), and Link's eating animation shows him getting stopped mid-bite from the toughness of it.
Item description: A dish gone awry after adding the wrong ingredient. Chewing your way through this won't be fun, but it'll fill you up when you're between a rock and a hard place.
- In Master of Orion, the Silicoids and custom Lithovore races subsist on rocks instead of organic crops, which frees the race from devoting population to farming. Lithovore races also lose access to farming-related technologies, but that's only an issue if the empire tries to assimilate food-eating aliens.
- Oxygen Not Included:
- The worst food item in the game is the Mush Bar, which is essentially actual dirt and water mushed together and processed into something vaguely edible. Duplicants can survive off them, but will hate the taste and probably get diarrhea. Deep-frying it makes it slightly more edible, and significantly reduces the intestinal distress involved.
- Hatches are critters you occasionally find at night that eat dirt and other minerals, and excrete coal.
- The Geodude evolutionary line and many other rock types eat rocks and soil.
- Sableye eats gems, and is thus considered a plague by miners whose diggings it moves into.
- Larvitar. According to the Pokédex, it won't evolve into Pupitar until after it's consumed a mountain's worth of soil.
- Aron and its relatives eat iron, which makes them a nuisance to railroads. Nosepass apparently uses its magnetism to attract its prey to it, which suggests that it eats mineral-based creatures.
- Rayquaza is suggested to eat meteors by Zinnia, and it swallows one in Omega Ruby/Alpha Sapphire in order to reach its full power. Whether they are its primary food source or just a method it uses to power itself up is unclear.
- Stardew Valley: Because of a programming oversight, Abigail accepts gifts of precious stones with "This looks delicious!" The fans loved it, so the creator added another line to Abigail's married dialogue asking you to bring her "something tasty" from the mines.
- In a Pebble and Wren strip, the title characters are pretending to be on another planet and Pebble wonders if the rocks are edible. Wren says no.
- Stand Still, Stay Silent: This gets discussed a couple times:
- When the cast City Mouse complains about having to eat dry rations, a more experienced member of the crew tells him he shoudln't complain unless they are reduced to eating dirt.
- When an more outdoorsy member of the crew decides to go out in the wilderness with no supplies besides his rifle, the others wonder about what he plans to eat. He plans to scavenge food, but the closest thing he currently has to a Translator Buddy misunderstands and thinks he plans to eat dirt.
- The Adventure Zone: Balance: Upon collecting the Philosopher's Stone, Magnus wraps it in a glove, uses the Glutton's Fork (which allows the user to turn non-magical items edible), and eats the whole thingnote . Problem being, the Philosopher's Stone is one of the most powerful magic objects in existence, and as a result, only the glove around it turns edible, meaning Magnus just swallowed a rock. Reality Ensues when Taako and Merle end up having to use some incredibly creative spell-combinations to get it out before it completely wrecks Magnus's digestive system.
- American Dad!: In one episode, Stan is searching for the gold Oliver North buried beneath the house and at one point concludes that "if I eat all the dirt, then all that will be left is the gold!" It seems that he's undergoing Sanity Slippage as the family watches it on tape- then Stan marches into the kitchen, having found the gold. He promptly flips everybody in the room off, multiple times.
- Aqua Teen Hunger Force: Meatwad eats Sand-Cakes at Shake's insistence. Subverted, as he knows it tastes terrible, there's no nutritional value and it'll probably kill him. Meatwad's just that stupid.
- In Ben 10: Omniverse, the Gourmands of Peptos XI have a... unique strategy for avoiding planetary conquest: they eat their own planet and belch their way to a new one. Just like the last ten.
- The Flight of Dragons: Dragons eat limestone and will swallow gemstones to help digest them, much like birds eat grit to grind their food. Said limestone produces the gases necessary for them to fly and breathe fire.
- Futurama: In "Lrrreconcilable Ndndifferences", after Lrrrnote accidentally conquers Earth the next thing we see is the main cast sentenced to the mines to supply his wife with gemstones to eat.
- My Little Pony: Friendship Is Magic:
- Gemstones seem to a dietary staple of the show's dragons. It first shows up in the early seasons with Spike, who treats gems and jewels as tasty snacks — among other things, he seems to enjoy them baked in pastries like sapphire cupcakes and jewel cakes, and once mentioned aging a ruby like someone else would age wine. Other dragons are seen doing this throughout the series, leading to some humorous misunderstandings in "Triple Threat", when the Dragon Lord Ember visit's Twilight's crystal castle and mistakes the castle's building materials for a banquet. It's lucky for them that large, flawless gems are common as dirt in Equestria — you can reliably get bucketloads of orange-sized gemstones from a few hours' digging around in some spots.
- In "Make New Friends but Keep Discord", the Smooze eats shiny things like jewels and gold — Discord keeps it placated by feeding it a diamond every once in a while, and it grows to ridiculous sizes after being accidentally closed in a closet full of golden ornaments and eating them all.
- Pinkie's sister Maud chooses and eats a rock from a basket of muffins at one point and has taught Pinkie the family's rock candy recipe — which uses rocks as the key ingredient. In "Hearthbreakers", it turns that the whole Pie family does this — Pinkie Pie's father at one point just straight up munches on a rock like it was a biscuit.
- The Ren & Stimpy Show: In "The Royal Canadian Kilted Yaksmen", the eponymous duo are stranded in the wilderness and slowly starving to death when Ren hits upon an idea. What, he asks his compatriot, is "Canadia's most abundant natural resource? "Dirt?" asks Stimpy hesitantly. "Yes!" replies Ren triumphantly. "We'll eat dirt!" It goes better than you'd expect.
- Wile E. Coyote and the Road Runner: In one short, Wile E. Coyote bakes a clay chicken and tries to eat it — and then bakes a clay trash can and dumps it.
- All humans, and most other animals, have a biological need to consume at least one type of naturally-occurring mineral: salt. More specifically, the sodium ions are absolutely vital for maintaining a healthy nervous systemnote .
- Earthworms combine this with their means of locomotion; they swallow the dirt in front of them, filter out any organic matter and defecate the rest out of the other end.
- There's a disorder known as Pica that causes people to crave and eat things that aren't normal food; often, this is dirt or rocks.
- Many animals, including most birds and several reptiles, have stomach-like organs known as gizzards, which lack the powerful enzymes and muscle actions that true stomachs have to break down food. For this reason, many creatures with gizzards swallow stones (known as gastroliths) to help crush the food in the gizzard. As a side-note to Harry Potter fans, this is why bezoars can be found in the stomach of a goat. This is also why ostriches supposedly eat diamonds. In practice they just like to eat hard stones for their gizzards, and diamonds just happen to be shiny hard stones for them.
- The phenomenon of gastroliths has also been recorded in fossils, with many skeletons of herbivorous dinosaurs being found with polished round stones preserved in their gut. Some of them can weigh several kilograms and be 10 centimeters long.
- Some water-dwelling animals are known to swallow stones for buoyancy control rather than digestion, such as crocodiles and alligators, seals and sea lions, amphibians, and even plesiosaurs.
- Certain minerals of a "stone-like" nature can be consumed for medicinal purposes in Chinese herbal medicine, but only in small dosages which are boiled for hours. One such mineral, Gypsum (or, in TCM: Shi Gao), can notably be purchased in large quantities from the Home Depot, as it is mostly used as drywall.
- Eating small amounts of clay is a surprisingly-common habit for people in subsistence cultures, who don't receive a full daily supply of minerals from their usual diet. It's particularly common in pregnant women, who really need those minerals. Eating powdered clay is also an efficient remedy to relieve diarrhea and soothe stomach pains caused by an excess of digestive acids. It was once the active ingredient in Kaopectate stomach medicine.
- San Pellegrino sparkling mineral water. The bubbles are natural, a result of a mineral called calcium carbonate (also known as chalk and limestone). This also gives it a... unique flavor. It's very popular in Europe. Eating chalk is actually one of the aforementioned weird pregnancy cravings.
- Certain species of parrots eat clay. The Other Wiki has a picture◊ of a small flock of parrots happily munching away at a so-called "clay lick." This is because it's common for tropical plants to produce toxic alkaloids in their leaves and seeds, so animals that eat them then need to eat clay to neutralize the toxins. Native Americans probably learned to cook and eat poisonous wild potatoes with clay after observing this behavior in animals. While they did eventually develop non-poisonous domesticated potatoes, eating clay with potatoes is still a tradition in some parts of South America.