Remember that old joke about two people deciding which restaurant to go to?
Bob: But who wants to eat dirt?
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 consist 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.
Compare with Metal Muncher, which also involves eating a substance that comes from the ground. Both are subtropes of Fantastic Diet Requirement. Not to be confused with Tasty Gold, where someone bites down on a coin (without consuming it) to confirm that it's genuine.
- In Monster Rancher, Golem eats rocks like food, and consumes sand like a beverage.
- Toriko at one point in the manga, the protagonist is tasting some "Mochi Stones", which are edible stones with flavour and texture of mochi, while one of Teppei's full course entries (Elg Crystals) imply that edible minerals are nothing new in the Torikoverse. Eating the legendary food ANOTHER will allow the eater to sample, taste and obtain nourishment even from dirt and rocks.
- Asterix: In Asterix and Cleopatra, the legend of Cleopatra eating one of the most expensive pearls ever to impress the Roman Empire is played with by presenting Cleopatra as someone who regularly drinks whole pearls soaked in vinegar. At one point, she orders a drink containing seven pearls, which her food taster complains about because he doesn't like the taste of that many pearls at once.
- 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.
- Parodied in Superman storyline Kryptonite Nevermore, where all Kryptonite on Earth is transformed into iron. The next time Superman runs into a thug brandishing a chunk of Kryptonite, Superman smiles, snatches the rock and chews on it◊.
Superman: Looks good! Mind if I try some? Mmmm... Not bad! A trifle stale... And it could use a bit of salt... but all in all, a nice little snack!
- 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.
- Played with and ultimately averted in Stone Soup. A group of travelers come to a village and are refused food. As they have a cooking pot with them, they fill it with water, drop a stone in it, and place it over a fire. One of the villagers becomes curious and asks what they are doing, to which the answer is that are making stone soup. The travelers further say that stone soup is delicious, but does improve when carrots are added. Curious, the villager hands them a few carrots. Another villager walks by, and the same scenario occurs, only with a different ingredient, and so on and so on until every household's added something. It results in a tasty and filling pot of soup, which the travelers share with the village they've tricked into generosity.
- The eponymous space monster in the film Dogora is a sort of amoeba or jellyfish-like creature which eats carbon. While this could technically be anything made of carbon, in the movie it is seen feeding on diamonds and coal.
- 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?
- Glory from Jack of the Red Hearts eats fistfuls of dirt while she and Jack are relaxing outside.
- 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."
- Turkey Hollow: The monsters eat rocks, which is useful when Tim and Annie are kidnapped and held in a building with a rock wall.
- 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.
- Played for Drama in The Boy from Aleppo Who Painted the War. Adam is so malnourished that he bites his nails for the salty taste of the dirt.
- The Chronicles of Narnia: The walking trees eat soil and dirt. Prince Caspian even describes 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 titular character from Disgusting McGrossface is said to lick mud off his feet.
- 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.
- 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.
- Rihannsu: Lieutenant Naraht is a Horta, the Rock Monster from "The Devil in the Dark". As such, he eats dirt and rocks—or rather a synthetic substitute, due to being stationed on the Enterprise. He goes through a growth spurt after The Romulan Way on account of having burrowed his way halfway across Romulus to help exfiltrate Leonard McCoy from the Romulan Senate building; turns out natural dirt and rock is more nutritious to a young Horta.
- Roys Bedoys:
- In I Dare You, Roys Bedoys!, Roys claims that dirt is delicious, seemingly just to be contrary, so Wen dares him to eat some, which he ends up disliking.
- Discussed in Its Your Fault, Roys Bedoys!, where Flora asks, If someone told you to eat dirt, would you eat it?.
- 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".
- Doctor Who. In "It Takes You Away", the Doctor eats the local dirt and somehow deduces from this that the TARDIS has landed in northern Norway. She also deduces that, 25 miles away from their current location, there's an alpaca farm with a gift shop and bad Tripadvisor reviews. Her companions are used to her bizarre behavior by now so take this in stride, but politely turn down the dirt when she offers it.
- Dr. Ridlehuber from the Getting Together episode "Memories Are Made of This" believes in eating dirt. As he sees it, normally people eat plants, which eat dirt, so he's just cutting out the middleman.
- In Season 2 of The Great, Catherine's pregnancy leads her to develop Wacky Cravings for dirt. Being Empress, she has servants bring it to her in fancy trays, and chows down on it with silver spoons.
- 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.
- Saturday Night Live advertised Quarry, a cereal comprised entirely of rocks. "Better tasting, cause it's mined."
- Hortas from Star Trek are silicon beings that live in the deep rocks of Janus VI, digesting rock for sustenance. Once communication was established between the Human mining colony and the native Horta population, productivity soared.
- Ultra Series: A number of kaiju turn out to be lithivorous.
- 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.
- In Yellowjackets's 1996 storyline, a teammate notices Taissa eating dirt outdoors at night. Since she was having a dissociative episode, she doesn't remember doing this dirt. When the teammate tells Taissa what she saw, Taissa denies it happened, despite waking up with dirt under her nails.
- "When I Was Your Age" by "Weird Al" Yankovic claims that the singer was so poor they had to literally eat dirt "every night for dinner". Getting dessert was a punishment.
- One of the more grandiose stories that go around about Cleopatra is that she owned the two largest and most expensive pearls known during her lifetime and wore them as earrings. In order to impress the Romans, she invited Marc Antony for the most expensive dinner he'd ever attend. When they were seated, she took one of the pearls from her ear, crushed it, dissolved it in either wine or vinegar, and then drank it. Marc Anthony declined the other pearl, but agreed this kind of wealth wouldn't be matched.
- 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. Surprisingly Realistic Outcome occurs 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.
- 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; crystal dragons similarly prefer a diet of gemstones and ores over any other sort of food, while amethyst dragons prefer a mixed diet of fish and gems.
- This is a common trait among other dragon species. Pyroclastic dragons prefer to feed on meat, but can subsist on a purely mineral diet when they need to. Stone dragons feed mainly on rocks, and consider gemstones to be rare delicacies. Mountain landwyrms subsist on diets of mountain rock spiced with the occasional giant or dire bear.
- When most types of dragons reach the end of their natural lifespan, they will physically consume their entire hoard, including the gold and precious metals and gems that they have accumulated. The hoard itself seems to have some mysterious impact on their afterlife, as dragons who died of old age but were missing part of their hoard when they died tend to linger as undead ghosts until the missing value of the hoard can be replaced and eaten.
- Folugubs are large beetles whose long tongue turns any crystalline object it touches into a runny slime, which the folugub then ingests. In addition to the risk of seeing a dungeon's treasure vanish down a beetle's gullet, they're a particular problem to psionic characters due to most psychically-attuned gear being made out of crystal.
- 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.
- 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.
- The thoqqua, a native of both the planes of fire and earth, is a massive worm that subsists on a diet of rock.
- The delver resembles an underground excavator whose entire underside is a mouth that excretes a saliva that can dissolve the rocks and gemstones that it eats.
- Gorgons, which in Dungeons and Dragons are bull-like monsters covered in metalic scales, have a Breath Weapon that  turns living organisms to stone. They then break the resulting statues into pieces and eat them. Their saliva magically turns the rock fragments back into flesh.
- Pathfinder: In addition to creatures such as xorn, aurumvorax and metallic dragons maintaining their mineral-eating habits from D&D, other creatures get in on the rock-eating diet:
- Blue dragons can sustain themselves on mineral-rich sand as a last resort, which they strain through their teeth while burrowing beneath the desert when prey is particularly scarce.
- Gugs can eat rocks and draw sustenance from them, although they aren't ideal food and they'll typically only use them as a last resort in the absence of meat.
- 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.
- Warhammer 40,000: Troths, a variant of plant-like abhumans, are said to be able to digest and draw nutrition from soil.
- 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.
- In Deep Rock Galactic, it is implied that one of the uses for the Morkite that the dwarves mine is as an ingredient in Dark Morkite ale.
- 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 had a talking stone giant blocking the path to get to the Earth Cave. He wants a tasty ruby to munch on.
- 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.
- Grim Fandango: Manny's bar stocks a drink containing real gold flakes. "Only the best for my customers... my rich customers." You eventually have to drink some of it to set off a metal detector.
- 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 side quests: 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 considered unpleasant fare, in contrast to good old-fashioned rocks. 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.
- Daruk's journal says Link once tried rock roast, and liked it.
- 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.
- 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.
- Orthworm eats the iron within soil to maintain its metal body. In a case of Gameplay and Story Integration, it also can have the Earth Eater ability, which causes it to heal from Ground-type attacks that would otherwise have been a weakness.
- 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.
- StarCraft: Just like the other races, the Zerg harvest minerals and vespene gas to produce their units and structures. Since they're entirely biological, this is indisputably what's happening.
- Stellaris: Lithoid species require minerals for population upkeep, just as organic species require food. Since minerals are also used for construction and upkeep almost everywhere else, this adds a bit of a wrinkle to resource management. The Terravore civic turns them into borderline Planet Eaters, chewing into planets for a quick influx of resources, which when done enough times turns them into uninhabitable Shattered Worlds.
- Temtem: According to their Tempedia entries, the volcano-dwelling Banapi grazes on coal, while the cave-dwelling Occlura eats raw rock.
- Depending on their genetics, crystal blobs — and even cows, chickens, and sheep — in Verdant Skies may eat flowers... or wood, rocks, or minerals. The absurdity is lampshaded in the game text.
- Champions of Far'aus: Downplayed; After failing to capture and eat the protagonists, a pair of mountain trolls agree on rocks for lunch as the group makes their escape.
- 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 shouldn'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.
- 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.
- Dilbert attempted to engineer a super food to solve world hunger and introduced it to a rural country that seemingly had no crops of its own. It's only afterwards he learns they don't grow crops because the mud that's ubiquitous to the region is their food source and rich with all the nutrients they need, and his new crop tastes terrible and has drained all the nutrients out of it to grow, truly leaving them to starve.
- 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.
- In The Fruitties, the Fruitties are anthropomorphic fruits and veggies along with other plants, and thus are at the very bottom of the food chain. Instead of doing something like photosynthesis to make food for themselves, however, the Fruitties eat substances like sand and mud.
- 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.
- In "The Duh-Vinci Code", Fry apparently ate rocks before they met up with Leonardo Da Vinci, which Farnsworth thought was dumb. Farnsworth proceeded to punch Fry in the stomach after he mistook Leonardo Da Vinci for Leonardo Di Caprio, hurting his hand but causing Fry no pain, which Fry felt justified eating them.
- 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.
- Total Drama: In the episode "The Obsta-Kill Course", dirt is revealed to be Scott's Comfort Food. He later puts it on his ice cream in "Sundae Muddy Sundae".
- 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 .
- 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.
- "White dirt" (kaolin clay) meant for eating can be purchased in some supermarkets in the Deep South of the United States.
- 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 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.
- 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.
- 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.
- 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 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.
- Obviously, it can be happened with poorly cleaned food. There's a good chance at least a little dirt can go by undetected.
- Mountain ibexes have been photographed licking the side of a cliff—while standing on said cliffside—to get salt. As the now-memetic caption says, "They crave that mineral."
- In Haiti, cookies made from dirt or clay, salt and butter or shortening by the name of Bonbon Tè are popular as a meal replacement for those in impoverished areas primarily because of how cheap they are to produce in mass quantities. They're also coveted by pregnant women and children as nutritional aids for the reasons stated above.