This relates to a world in which there is no magic and only medieval technology. The ruling and religious classes want to convince the general populace that magic exists.

For example a sword-smith has been tasked with making a 'magical' sword that can only be drawn by 'the chosen one'.

Of course there is to be a secret mechanism that only those in the know can operate.

The problems

The sword has to be a top quality sword that is forged by standard methods before inserting in the stone.

The stone has to be real stone. It can be shaped using medieval tools but should be heavy enough so that it can't easily be moved. The sword must fit snugly.

The mechanism for releasing the sword must be very difficult to discover. Nothing so obvious as pressing a simple foot pedal.

A circle of six-foot radius is marked on the floor around the stone. Only one person is allowed in the circle at a time.

There are guards to prevent damage to the stone or sword but anyone whether commoner or not must be allowed to try. They can examine the sword and the stone carefully before trying, and they have three attempts each. The guards will only intervene to prevent damage or more than one person at once entering the circle.

The chosen one should not be allowed to try too soon. There must be many failures first to 'prove' it is magic.


How can a sword-smith use medieval technology to simulate a magical sword in the stone that can only be released (or put back) by someone who knows the secret? No actual magic is allowed.


There is some flexibility about the locale and the shape of the sword. I imagined something like the following but if it invalidates an existing answer I won't make the picture a factor when choosing. Add armed guards and possibly a large pavilion-tent to protect from the weather.

enter image description here

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    $\begingroup$ As the late Sir Terry Pratchett put it ‘What’s so hard about pulling a sword out of a stone? The real work’s already been done.' $\endgroup$ – Rekesoft Mar 12 '19 at 11:22
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    $\begingroup$ @Rekesoft, Lord Rust, at dinner with Edward d'Eath $\endgroup$ – Separatrix Mar 12 '19 at 11:31
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    $\begingroup$ You mention it needing to be real stone without explaining why. Would concrete be acceptable? It predates the middle ages and was then apparently mostly forgotten for several centuries. en.wikipedia.org/wiki/Concrete#Middle_Ages. So someone could easily pass it off as real stone, especially with some natural weathering, lichen, etc. This would make it easy to encase a custom mechanism $\endgroup$ – user43774 Mar 12 '19 at 18:01
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    $\begingroup$ @anjama - Concrete could be part of it as long as it is out of sight. The problem with making concrete look like rock is that lots of burly contenders will be standing on top of it to get a good grip. This will wear off any fake weathering or lichen. If you have a good mechanism that has rock on the outside and concrete inside then I'm certainly interested. $\endgroup$ – chasly - supports Monica Mar 12 '19 at 19:42
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    $\begingroup$ The "Chosen One" is actually a street magician who performs a trick to make the sword disappear, as it is actually a prop that retracts entirely when stepping on the cobblestones in the good order, and at the same time springs a whole sword from his sleeve, with the perfect combination of diversion and deception. $\endgroup$ – kikirex Mar 13 '19 at 17:55

16 Answers 16



  • One large hollow rock
  • One dwarf
  • One large pair of pliers
  • One tunnel
  • One loud voiced announcer of who is about to try to pull the sword out

Tunnel under the rock for your dwarf to get access, make sure he knows the name of the eligible person to release the sword for when the loud voiced announcer calls it out. All you need now is a mechanism for holding the sword in place while the dwarf is off duty.

“Nah, someone pulled a sword out of a stone,” said Nobby.
“How’d he know it was in there, then?” Colon demanded.
“It...it was sticking out, wasn’t it?”
“Where anyone could’ve grabbed it? In this town?”
“Only the rightful king could do it, see,” said Nobby.
“Oh, right,” said Colon. “I understand. Oh, yes. So what you’re saying is, someone’d decided who the rightful king was before he pulled it out? Sounds like a fix to me. Prob’ly someone had a fake hollow stone and some dwarf inside hanging on the other end with a pair of pliers until the right guy came along—”
Men at Arms, Terry Pratchett.


'Lock' the blade in place

Give the sword blade a fuller, the groove used to lighten some blades, and end it before the tip of the blade. It can then be inserted into a well crafted, close fitting, slot in the stone and a 'key' used to fit into, and interfere with, the fuller holding the blade in place in the slot.

Inside the stone there needs to be some mechanism to release the key holding the blade. In medieval times they had crossbows with heavy draw weights held by a 'nut and lever' mechanism. A modified version of this could be used, with a remote cable based release, to allow 'selective' drawing of the sword. Due to the strength and design of the locking mechanism no matter what force is applied the locked blade will not come free, actually the harder you pull the stronger the locking force.

It could even be made to self reset so that if the new King replaces the blade it again locks into place and again no-one else can remove the sword until the 'One True King'(TM) makes a second attempt.

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    $\begingroup$ @Kallum Tanton - the 'nut' mechanism for crossbows is a rotational release rather than a pinch release. The way I see this solution if there is no load on the blade the release will be silent - it just moves the 'key' to the side away from the fuller. If there is a load it will be almost silent and that would be lost in the fact it's embedded in the centre of the stone and that a steel blade being withdrawn from a stone hole is going to make enough noise to cover it. $\endgroup$ – GeeTee Mar 12 '19 at 13:16
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    $\begingroup$ But ... how do you create the abcess in the stone to begin with? The clean-close-fit sheath part seems problematic. Unless you have lots of grad students to use as drilliing and polishing slaves. $\endgroup$ – Carl Witthoft Mar 12 '19 at 15:37
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    $\begingroup$ @carl Witthoft - You will need a competent stone worker/carver to create the required blade hole and trigger cavity in the stone, but it's possible with the tools available. The harder the stone obviously the harder the task to shape it but humans have been shaping stones for a long time. Quite intricate stone moulds for metal casting have been in use since the bronze age. Look at some of the tracery and carvings on medieval buildings such as churches for the accuracy that they could achieve. $\endgroup$ – GeeTee Mar 12 '19 at 16:16
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    $\begingroup$ For an entirely "mystical" release, you could have the locking mechanism be metal, and use a lodestone - aka a magnet - to draw the lock in and out. The "One True King" merely sets his religious symbol beside the stone, then easily draws the sword! For bonus points, put the metal latch at an angle, so when he removes the magnet, the latch slips back into place, and anyone else trying to remove the sword after him has no chance. $\endgroup$ – ArmanX Mar 12 '19 at 20:32
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    $\begingroup$ I'd suggest getting rid of the cable: too great a chance of the fraud being discovered. In stead, while all the rubes are trying (and failing!) to pull the sword out, the One True King (TM) will actually <i>push the sword in slightly!</i> People will wonder what kind of Hercules this is! -- is he trying to make the task that much harder!? Pushing the blade in presses down on the fuller release mechanism allowing him, with suitable grunting and sweating, to lift the sword from the stone. Pushing the sword back in trips the mechanism again to reset. $\endgroup$ – elemtilas Mar 15 '19 at 13:20

Seal the sword in limestone

Limestone dissolves in acid, which medieval peasants likely will not know. Fortunately our sword-puller does. Via some mechanism or his own doing, vinegar can be poured onto the limestone to dissolve it and weaken the hold on the limestone enough to wrench the sword free. It will bubble, however, so the limestone may need to be below a layer of decorative stone.

As some display they may take a swig then pour it onto the sword. Or maybe trigger some hidden pipe below the surface.

Edit: The dissolving reaction will not remove all of the stone, only enough to weaken its grip on the sword.

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    $\begingroup$ I like this! the sword may have a subtle thickening at the tip, to make the 'grip' of any acid-solvable glue quite formidable, and the acid (wine might suffice and would not be totally out of character for the applicant to smell of) could be transported soaked into the gloves (special soaky lining?), dripping down along special grooves on the sword that could pass as ornamental. $\endgroup$ – bukwyrm Mar 12 '19 at 12:53
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    $\begingroup$ Also, the 'stone' can be made from burnt mussels and sand, in effect looking (and for most purposes being )sandy limestone. $\endgroup$ – bukwyrm Mar 12 '19 at 12:56
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    $\begingroup$ Interesting idea, but how do you get it locked into the limestone in the first place? Also, I suspect the reaction rate would be too slow for an effective one-man display. It would take a least a couple minutes to eat all the way down the length required for a solid grip, during which time other challengers are likely to become suspicious unless the True King has enough showmanship to cover or play up the fizzing rock as part of the "magic" happening. $\endgroup$ – brichins Mar 12 '19 at 17:35
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    $\begingroup$ Some examples may be: An ornamental hole in the sword has a sandstone cylinder going through, preventing it from coming out. Or maybe the fuller of the sword has sandstone laid in it, such that when pulling it out the sandstone blocks its travel. All of these require some decent stone-work, but I'm sure are feasible. Also see @bukwyrm s suggestions. $\endgroup$ – Howard P Mar 12 '19 at 18:00
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    $\begingroup$ @brichins use a clear acid, like vinegar. Pretend its holy water. Kneel down and pray for a few minutes while you wait for it to work. Now you're king by clearly divine means as well. $\endgroup$ – Myrdden Wyllt Mar 12 '19 at 18:24

Forge a blade with a very slight reverse taper, so that it's ever-so-slightly wider at the tip than at the hilt. To the casual eye, the blade should appear straight and constant width, but should be just enough wider at the tip for your blade trap to hold it in place.

Now, choose a stone with a very rough texture. The reason for this is you're going to split the stone in two, preferably in an uneven and non-obvious pattern, and you don't want the seam to be noticeable. Inside the split, carve your grooves for the blade. You'll need to be very precise as the sword should fit very snugly into the grooves.

Finally, you will need to sand off a very thin layer on the cut side of one or both halves of the stone, so that they lean towards each other, applying pressure on both sides and trapping the tapered blade between them.

Stone Layout

Now the trick: In order to remove the sword from the stone, you will need to place one foot on each half of the stone and push them apart. If they are large and heavy enough, the stones should barely need to move to release the pressure. To the untrained eye, it will seem that your arms are doing the work of pulling the sword upward, but in reality, it is your legs pushing the stone halves apart that free the blade to be easily drawn.

To discourage other people from mimicking your stance, your "king" should be wearing a robe that covers his feet, and the stone should have naturally comfortable obvious footholds that are both on the same half, so that people will not think not to use those but instead must stand in a less obvious and less comfortable position in order to push the stones apart.

As with any good "magic" trick, some practice may be required to make the act seem convincing. A little showmanship and sleight of hand (or foot) goes a long way if you know what you're doing.

  • $\begingroup$ This seems risky if the only thing preventing a commoner from defeating it on accident is proper stance. $\endgroup$ – brichins Mar 19 '19 at 19:42
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    $\begingroup$ If you make the split uneven so most of the stone near the blade is on one side (I added a picture for clarity), you can make this far less likely. Also make that thin sliver uncomfortable to stand on so you can't get a good purchase on it unless you're really trying to do specifically that. $\endgroup$ – Darrel Hoffman Mar 19 '19 at 20:27

The sword looks like this: Two-handed great sword, Source: knifeworks.com

The parrying hooks can be inserted below the stone's surface, where they lock into whatever locking mechanism you desire. Thus, anyone simply pulling on the handle will be unable to move the sword. Only the correct sequence of movements, such as pushing or turning the sword, can then release the lock, allowing the blade to be pulled out.

With some practice, these movements could be performed such that they seem natural to observers. Alternatively, with the right “ritual instructions“, not even the Chosen One needs to know about the trick.

One minor disadvantage though: The stone cannot fit perfectly to the blade, as some space must be allowed for the parrying hooks. However, this can easily be explained by saying that obviously these grooves were made by the same hooks when the sword was pushed into the stone in the first place.

Even better: This mechanism can be made fully reusable, establishing a tradition of choosing the royal successor this way over multiple generations.

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    $\begingroup$ So it's childproof. $\endgroup$ – Mike G Mar 12 '19 at 20:01
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    $\begingroup$ I like it - the sword fits into the stone like a key in a lock. A complicated 'twist' pattern would keep people from trying too hard, and whoever is watching over the stone can reset it if someone realizes they can twist it. $\endgroup$ – ArmanX Mar 12 '19 at 20:27
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    $\begingroup$ I don't like this. As anyone who got a key stuck in keyhole or solved 3d puzzles, pulling such a locked object around gives a "feel" of the shape of the internal stuff. This feel will look mighty suspicious and instantly recognizable as a lock for anyone with experience with locks, and someone with enough locksmithing (or lockpicking!) experience may actually solve the puzzle. $\endgroup$ – ivan_pozdeev Mar 13 '19 at 5:10
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    $\begingroup$ @ivan: This problem is mitigated by the following factors: The lock can be made to fit tight to both the blade and the hook, reducing wiggle room to next to nothing. The first movement can require an amount of downwards force or torque which is unlikely to be applied by anyone simply pulling. Both the lore and the practical setup of the sword can be crafted to discourage random experimentation. Of course, this is not completely foolproof if someone already susppects foul play, but so are the other options proposed. $\endgroup$ – Surpriser Mar 15 '19 at 11:28

The stone has only to be the cover of a tub filled with a dilatant liquid.

A dilatant (dī-ˈlā-tᵊnt) (also termed shear thickening) material is one in which viscosity increases with the rate of shear strain. Such a shear thickening fluid, also known by the initialism STF, is an example of a non-Newtonian fluid. This behaviour is usually not observed in pure materials, but can occur in suspensions.

An example of dilatant is oobleck, a mixture of water and starch:

A person may walk on a large tub of oobleck without sinking due to its shear thickening properties, as long as the individual moves quickly enough to provide enough force with each step to cause the thickening.

The faster the candidate will try to pull out the sword, the more the liquid will hold it in place. Just give the surface of the blade adequate roughness.

Just instruct the chosen one to sloooowly pull out the sword. "Patience is the key!"

Starch was a luxury good in middle age, used for starching clothes. Since you are going to pick a king, I see no issues in using a luxury good.

  • $\begingroup$ Ah yes. They could also mutter an impressive-sounding chant as they did so, e.g. "Slowly, slowly, comes the sword, Slowly, slowly to its lord" etc. $\endgroup$ – chasly - supports Monica Mar 12 '19 at 11:25
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    $\begingroup$ P.S. (a) Was there medieval oobleck? What specifically could it have been made from? (b) Is there an effect whereby a long strong pull would fail and yet a long weak pull would succeed? This would defeat people who made sudden movements but it would also defeat persistent types who pulled for a long time but too strongly. $\endgroup$ – chasly - supports Monica Mar 12 '19 at 11:44
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    $\begingroup$ The 'give' of dilatants is noticeable, and would encourage people to go slow, as the experience of pulling things out of muck (poor mans oobleck) is quite relatable to the average swineherd... $\endgroup$ – bukwyrm Mar 12 '19 at 12:50
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    $\begingroup$ Swords generally taper - the oobleck's effect would be greatly diminished because of this. You may end up with more effect of suction (like quicksand) than you would with shear thickening. $\endgroup$ – David Rice Mar 12 '19 at 14:23
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    $\begingroup$ There is no way starch would hold against a man pulling with his entire body strength $\endgroup$ – Andrey Mar 13 '19 at 19:27

Make the platform that people stand on while trying to pull the sword a slight rocker. That is, while people stand on it, it tilts forward (by a millimeter or two), pressing against the sword and locking it (either by pure friction, or by a mechanism with parrying hooks like in Surprisers answer).

Now of course, the guards are standing on the platform as well, making sure that even if a light weight child tries to pull, the sword is fixed.

The future king will command the guards back, to the other side of the plaform. This will make it tilt back for a millimeter and release the sword.


A different idea. There is a release mechanism embedded in the sword hilt. It basically has a hook that comes out from the side of the blade of the sword, blocking it inside the stone, and which can be triggered somehow.
Using a trigger is too risky: people could notice it and even realize that using it they can extract the sword. But it could use a kind of lock. I have two proposals

  • The Chosen has a ring that can act as a key: it has an opportunely shaped extrusion that can be inserted in a lock inside the hint, which allows to release the hook that forces the sword inside the stone
  • The Chosen has a ring made of magnetic iron. The mechanism in the hint has a kind of cavity with a metal rod, which is is attracted and moved upward, this way unlocking the hook. This last one is probably less suitable, beacuse the mechanism would need to be light in order to allow for the magnetic ring to attract the iron, but in this case it could be too fragile and easy to break if enough force is used to pull the sword

Or, if you like a less serious plot twist (even if it was explicitely forbidden by the OP): the sword is in reality a screw, and the Chosen is the only one who knows that he hasn't to pull the sword, but only unscrew it... :)

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    $\begingroup$ I personally like the magnet idea but I would have put it in his boots. With a specific spot he has to put his foot to unlock it. $\endgroup$ – James Khoury Mar 12 '19 at 22:52

The sword is placed in a scabbard. At the bottom of the scabbard, there is a spring loaded push pin lock - when the sword is pushed all the way down, it pushes the pin back until it reaches a hole in the sword, then it springs back and locks the blade in the scabbard. The scabbard has a thread on the outside.

You pour a large concrete block or you pick a large rock and you drill a threaded hole. Concrete might be easier since you can create a metal jacket that you can set in the concrete. You tighten the scabbard into the rock.

Threaded fasteners were unknown in the medieval world, nobody would think to rotate the sword, they'll all try to pull it out.

Whoever is rigging the selection can reinforce the notion that the sword is meant to be pulled out by spreading rumors among the populous:

"Surely lord Clegane will be the next king! He is so strong he'll pull it out with one hand!"

"Lord John's servant told my wife's aunt the lord is drinking bull's blood. His witch told him it will give him the strength to pull the sword out and become king!"

Then reinforce it some more with some official announcements. Have the criers announce:

"Thou who pulls the sword out by his bare hands shall have the strength to be king!"

Give this a few months to work, then announce the contest is open. Have the soldiers overseeing the line of candidates give the following instructions to each man:

"Hurry up peasant! I don't have all day! You know the rules - you have 3 pulls - hurry up now, there are 100 more like you waiting!"

Feeling rushed and excited, the peasants have no change. Then you give some of the dumber aristocrats a go - again manipulating them to use brute force.

"Lord Stark! You were glorious at the battle of Sherlock. No man is as strong as you! Give it all your might and surely the stone will yield to you!"

Obviously, while still in front of witnesses, the nobles will be given more time and privacy for their attempt. Make the circle around the sword where people are not allowed bigger - say 50 ft. When your candidate of choice is to attempt, he'll be far enough that nobody will be able to see how exactly he pulls the sword out - but still close enough that there will be no question that he did gain the sword by himself.


Metal expands when heated.

Let's assume that the sword was placed into the stone after being cooled. When it heads up to room temperature, the metal in the sword expands so that the fit goes from 'snug' to 'stuck'. Regular trials can be held at midday, let the rock be in the sunlight. Pulling on the sword will cause friction, and add more heat.

Cooling down a big rock takes time, and without technology there's only so much you can do. Keeping the rock out of the sun or having a trial at night might work. There might be a mechanism where they can cast a shadow over the rock for one day. They might be able to run water underneath the area that cools it. The temperature difference might be very small but it becomes just enough to be able to pull it out slowly with no resistance.

Using this method, the guards will need a day's notice of the chosen one's trial and will not be able to hold any other trials that day.

  • $\begingroup$ interesting idea... on the other hand, a cloudy or overcast day would be quite troublesome to one's plans, even if rainy ones were (somehow) prohibited. Or even a sunny-but-colder day, as often occurs in spring or autumn. $\endgroup$ – Megha May 26 '19 at 1:00


The sword is inserted into a shaft in the stone, which is filled with resin/rosin and left to harden. The resin is not visible from above, the shaft narrowly fitting the sword, and the surface covered with stone dust set in the resin.

Your hero arrives with a large medieval quartz lens atop a long wooden shaft, garbed in flowing robes, sporting a pointed beard, and generally looking the part. Wide-eyed onlookers stand enthralled as your hero steps into the ring. Nonchalantly planting his staff into the ground, unbeknownst to the crowd the sun's rays on that historical summer day focus upon the blade of the sword, whose temperature begins to soar. Your hero approaches the rock and begins to make strange incantations in a foreign-sounding tongue, dramatically flailing his arms around and occasionally rushing back towards the startled crowd with a demonic wail. Once the temperature has risen sufficiently, the melting rosin begins to emit a faint odour. On this cue, your hero tentatively wraps both hands around the grip of the sword and begins to tug. It slides out leaving a sticky ichor as though the stone was wounded by his dark magic. The astonished witnesses let out a gasp and collapse to their knees, while your hero towers above them, sword held aloft. "Hail, King!" they cry, while your hero cries "En-guh-land!!!" in ancient tradition.


A magnetic latch.

Unlike what others have suggested with using electromagnets to keep the sword in place, this would work in a medieval setting. Find 2 natural magnetic stones. Use a sword that has a a wider part of the blade or any other decoration that could be latched in the stone. Attach a magnet to the latch.

When the true king comes he will have a magnet in his gauntlet. When drawing the sword he will place his hand on the stone. The magnet will pull the latch and free the sword. This can be as simple as pulling a pin out of place. It can then freely be drawn.

At this time magnets should be obscure enough that most people would not even think of it. Even if they did they would need to know the exact spot to place it. As OP mentioned in comments the stone would be guarded from people snooping too hard.


Thermal expansion is it!

  1. Choose a rock with hard material that withstands heat.
  2. Put the rock over a hot fire and let it heat up. The warmer, the better. Thermal expansion will apply.
  3. Drill the hole for the weapon in the hot stone, exactly as wide as the sword is.
  4. Put the sword in the hole.
  5. Let it cool and shrink. The hole will tighten on the blade from every side, holding it with a force insuperable for mortal beings.
  6. Put the sword outside, possibly in a cold environment for maximal effort.
  7. ???
  8. Profit

Pulling the sword out is easy if you know the trick: just make a fire around the stone, let it heat up again, and you can easily pull out the weapon. Be careful though - hot swords look exactly like cold swords!

The though part is selecting a mineral with greater thermal coefficient than the steel your sword is probably made of, so the heating will actually release it. According to this site, steel has a thermal coefficient of around 11-12 m/°C. Granite (7.9 m/°C) won't do it, limestone is a good candidate (11.4 m/°C), but I suppose it's a bit too brittle for this. Marble has a range of 5.5 - 14.1 m/°C, which is quite promising. Considering the wide variety of stones around, you probably can find a suitable one.

  • $\begingroup$ This will let you secure the sword without difficulty, but pulling it out is a different matter. Steel has a higher coefficient of thermal expansion than rock, so when you heat the sword in the stone, it will lock even more firmly in place. $\endgroup$ – Mark Mar 13 '19 at 20:27
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    $\begingroup$ @Xen2050 When you heat up a material with a hole in it, the hole will expand just like if it was filled with the material around it. Check this question: Will a hole cut into a metal disk expand or shrink when the disc is heated? $\endgroup$ – Neinstein Mar 14 '19 at 12:15
  • $\begingroup$ @Mark oops, I kind of forgot about that :p Considering how much kind of mineral are around there though, one probably could find one with greater expansion coefficient than steel (11-12 um/°C). Sandstone is a good candidate (11.6 m/°C), though it's not really resistant. (scource) $\endgroup$ – Neinstein Mar 14 '19 at 12:28
  • $\begingroup$ @Mark Would you please re-consider your downvote (I assume it was yours) in spite of my recent edit? If you still think my answer needs improvement, how could I make it better? Thanks :) $\endgroup$ – Neinstein Mar 16 '19 at 13:10
  • $\begingroup$ Since you found a stone that's both reasonably common and has suitable thermal performance, sure. $\endgroup$ – Mark Mar 17 '19 at 5:29

Without looking at all the other answers here. It could be possible to place a sword into a stone that is melted like lava. I imagine the stone was not brittle.

All one would have to do is add sand to liquid iron or bronze enough to give it a more Stoney texture and appearance. The differences in temperature from the sword and molten Stone would be enough to keep the sword from adhering to the stone on a molecular level.

The best time to pull the sword what day wallet it was in the middle of winter maybe on a unusually cold day when nobody is willing to come out and try. The best time to have a sword pulling contest would be in the middle of summer.


Magnets, how do they work?

I don't remember the exact story, but I know I read a version of this. Basically you construct the rock w/ an electromagnet in it, and until the "guardian" switches off the magnets the sword can't be pulled out.

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    $\begingroup$ medieval electromagnet? $\endgroup$ – Andrey Mar 13 '19 at 16:35

Concrete would be available to them, and is quite capable of holding that sword in place. The ancient Romans had concrete, and while not common in the medieval era, its knowledge need not have disappeared.

Just put the sword in a mold, pour concrete around it, and have a stone mason work the result until it looks like the shape of rock you want. You can even paint it to look more like a natural rock if you want, or clad it in natural stones.

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    $\begingroup$ Okay but what is the release mechanism? Only one person should be able to draw the sword. If it is set in concrete, either no-one could or the first strong person to try could. $\endgroup$ – chasly - supports Monica Mar 12 '19 at 11:32
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    $\begingroup$ Please read the question carefully. There is no real magic. The whole idea is to fake magic. Also this happens in medieval times and I'm pretty sure they hadn't invented electromagnetism then unless you can convince me otherwise. $\endgroup$ – chasly - supports Monica Mar 12 '19 at 11:39
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    $\begingroup$ @chaslyfromUK : I just worked out the specs for an electromagnet that would be guaranteed to hold the sword in place. It works out to about 10 million ampere-turns at about 75 kV. Not unless you've got a large generator or at least a large capacitor hidden somewhere and are planning to move the sword away when not in use. $\endgroup$ – nzaman Mar 12 '19 at 13:37
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    $\begingroup$ The problem with an electromagnet (besides not existing in the stated historical timeframe) is that every time someone clad in armor attempted to remove the sword, they'd become just as stuck to the rock as the sword itself was. And the circle should probably be bigger than 6 feet, or else your guards are going to be stuck to the rock too, or at least get really tired resisting it's pull. You'd better have your One True King (TM) try relatively early, or he's going to have a lot of shiny knights to remove from the rock before pulling out the sword. $\endgroup$ – dwizum Mar 12 '19 at 14:00
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    $\begingroup$ @dwizum but only the true king can untangle the mess of knights and guards around his fated weapon! $\endgroup$ – Patrice Mar 12 '19 at 14:28

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