How to extract the iron out of blood to make a sword from one's foes?

[Coidzor]

And other uses for mass quantities of blood.

So, given a quasi-Medieval, pre-Industrial setting, aside from just using magic itself, how could one potentially go about extracting various things, most notably iron, from Industrial quantities of blood? Without shrugging and creating some magical process that does it directly?

What other uses would present themselves? I'm aware that some paints may have used blood as a binder at one point or another and I know about blood sausage and other foods made from processed or cooked blood. I believe it can be used as a fertilizer to some extent, possibly in the form of blood meal which is also feed for some animals.

[dropbear8mybaby]

Rust Monsters.

[Martin Greywolf]

You can't. Iron in blood isn't free floating (boy, that would cause some problems), it's mostly in the for of hemoglobin, a fairly complex protein. To get any workable iron out of it, you first need to destroy that, which I have no idea how to do, but I do know that it would need a knowledge of biochemistry far beyond pre-Industrial capabilities.

Also, Rust monsters would do bugger all, since rusting is oxidization and proteins can't oxidize, as far as I know. Bonus points for sillyness, though.

[RazorChain]

You get mineral iron from food and the body converts it to hemoglobin. So why not just extract the mineral iron from food in the first place, easier than changing proteins to iron.

If you really want to extract iron from blood then just make a thingamajic device that does it. Don´t explain the science. Just like using humans as batteries (stupid)

[Iruka]

I did some googling and apparently a lot of people are interested in forging swords from blood.
However I couldn't find any conclusive answers. (Beyond the fact that you need to kill about 360 men to forge a sword.)

So here is my guess based on half remembered stuff from chem lab:

1. Dry the blood
2. Burn the dried stuff. You now have a lot of ash containing some iron oxide.
3. Put the ash in water and separate the heavier iron oxide with some kind of peasant-powered centrifugal contraption.
4. Proceed with the powder now mostly containing iron oxide as you would normally in the steel making process.

Will probably not hold up under the scrutiny of a chemist, but might be sufficient enough for suspension of disbelief.

[MrStabby]

Hmm. Depends on the system.

In D&D use a spell that deals acid damage to create a soluble iron salt. Electrolyse said salt using call lightning or similar spell?

Otherwise I would suggest roasting the blood at very high temperatures and low pressures, but not certain how effective it would be. I also think you could heat it in the presence of oxygen to create an oxide then pass carbon monoxide over it.

[The Great Wyrm]

1. Dry the blood
2. Burn the dried stuff. You now have a lot of ash containing some iron oxide.
3. Put the ash in water and separate the heavier iron oxide with some kind of peasant-powered centrifugal contraption.
4. Proceed with the powder now mostly containing iron oxide as you would normally in the steel making process.

Actually, this does hold up under my scrutiny (and I'm a chemist). Step 3 would be the most difficult part given the technology level. Iron oxide is insoluble in water whereas most other components of ash are soluble, so this would help. Thankfully, you don't need to get it to very high purity.

[Donnadogsoth]

Actually, this does hold up under my scrutiny (and I'm a chemist). Step 3 would be the most difficult part given the technology level. Iron oxide is insoluble in water whereas most other components of ash are soluble, so this would help. Thankfully, you don't need to get it to very high purity.

Just how many foes worth of blood would you need to make a sword out of it?

[Geddy2112]

Just how many foes worth of blood would you need to make a sword out of it?

An average adult has 4-5 grams of iron in their body, around 2.5 grams is in the blood as hemoglobin, the rest is scattered about, primarily in bones and liver.

So if you were able to get 100% efficiency in extracting all the iron in a person(assuming 4.5g average), and you were making a 1 kilogram weapon, you would need 222.23 people to make one weapon.

If you are only draining blood(2.5g per person), you need 400 people.

I second drying the blood, then baking it to ash the organics, then you can dissolve the remaining salts in acid or water and precip them out, or wash the soluble salts from the iron. Then melt the iron and get to forging.

[KnotKnormal]

You can't. Iron in blood isn't free floating (boy, that would cause some problems), it's mostly in the for of hemoglobin, a fairly complex protein. To get any workable iron out of it, you first need to destroy that, which I have no idea how to do, but I do know that it would need a knowledge of biochemistry far beyond pre-Industrial capabilities.

Actually, extracting iron from the blood is quite easy. you just need an enzyme that will collect the Iron from the Hemoglobin. My friends and I actually discussed this in great detail recently even considered contacting the red cross to see if they would want to set up a special blood drive, where we could take the other wise unusable blood and extract the iron. the process is surprisingly simple and the materials needed are much cheaper then you might expect.

[Cernor]

Actually, this does hold up under my scrutiny (and I'm a chemist). Step 3 would be the most difficult part given the technology level. Iron oxide is insoluble in water whereas most other components of ash are soluble, so this would help. Thankfully, you don't need to get it to very high purity.

I would have suggested separating the plasma and red blood before doing anything else: would burning the blood get around this issue, or would that leave unacceptably high levels of carbon in the steel?

[Strigon]

You can't. Iron in blood isn't free floating (boy, that would cause some problems), it's mostly in the for of hemoglobin, a fairly complex protein. To get any workable iron out of it, you first need to destroy that, which I have no idea how to do, but I do know that it would need a knowledge of biochemistry far beyond pre-Industrial capabilities.

I don't know about that. People have been inadvertently doing some pretty impressive stuff with chemistry long before anyone had any idea how atoms even worked on a rudimentary level; happy accidents and trial and error can get you pretty far when an entire civilization is doing it.
Granted, I don't know if anyone would know whether or not there actually is iron in blood, and figuring out how to access it would likely take a lot of guesswork (although the burn-and-sift method is pretty much standard procedure, so it might not take all that long to figure out).

What I'm saying is, somebody else would have had to take note of that way to get iron from blood, at least out of academic interest. It doesn't have to be common knowledge; even if it's just something your apothecary friend down the street happened across, it's extremely unlikely your character would stumble upon it.

[Cealocanth]

So, according to this article, a solution containing hemoglobin already has a small concentration of free iron nanoparticles, which can be gathered through the use of a strong magnet.

However, to separate all the iron from solution, first the use of a surfactant must be used to destroy all cell membranes, and then the resulting solution must be filtered to remove all proteins and things that are not hemoglobin. Then, the hemoglobin solution must be treated with an acid-permanganate-mediated digestion of the hemoglobin, which results in the release of most of the iron from the iron pockets of the hemoglobin. The resulting iron can be separated with a centrifuge combined with a powerful magnet, which will yield about 625 mg of nanoparticles per L of blood.

Then you need to put the solution containing the suspended nanoparticles (which will likely be a bright orange color) through a strong reaction with oxygen. This can be done by heating and allowing the solution to react with air by occassionally mixing, or by the addition of some DI water for a similar reaction, or through the addition of peroxide. The result should be recrystalized iron oxide, which can be filtered out of solution with a fine filter after it is cooled rapidly.

Then you treat the iron oxide just like in any other blacksmithing scenario.

So, there you go. A recipe for extracting iron from blood from a chemical engineering student.

Edit: That 100 microgram measurement comes from the amount of iron bound to transferin, not the overall quantity. As far as what I can tell, each human has 2.5 g of iron in their blood, about 625 mg per L of blood. This would leave 2540 L of blood necessary to make a 3.5 lb sword, or abbout 650 adult men worth of blood. That is, adult men that have been well nourished during their lifetimes. In the middle ages, this is very possible to not be the case. You're probvably looking at about 800-900 people worth.

[Storm_Of_Snow]

Probably ballpark it at a thousand.

As for impurities, could some of them be beneficial for the chemical composition of the steel, while the rest could be removed as slag during refining?

Also, Rust monsters would do bugger all, since rusting is oxidization and proteins can't oxidize, as far as I know. Bonus points for sillyness, though.

Oxidation is loss of electrons, which any molecule can be subject to under the right conditions.

But you would have the job of extracting the iron from the rust monster.

[Strigon]

Probably ballpark it at a thousand.

As for impurities, could some of them be beneficial for the chemical composition of the steel, while the rest could be removed as slag during refining?

I mean, probably. But where would you even begin identifying, much less isolating, those impurities?

[ExLibrisMortis]

Granted, I don't know if anyone would know whether or not there actually is iron in blood, and figuring out how to access it would likely take a lot of guesswork (although the burn-and-sift method is pretty much standard procedure, so it might not take all that long to figure out).

Well, blood does taste like metal, doesn't it? That can't be a coincidence... and then, as you say, burn-and-sift is standard procedure.

Maybe some alchemist/blood mage was convinced he'd found the unique 'metal of life', and then disappointedly found that it was pretty much just iron?

[ATHATH]

Do keep in mind that many fantasy universes have divination magic available.

[Cealocanth]

I mean, probably. But where would you even begin identifying, much less isolating, those impurities?

You would basically have to remove them the same way that impurities are removed from most metal samples. The sample is heated to a liquid state, and everything that boils or has a smoke point below that temperature vaporizes off. That handles most impurities. Silicates and similar, which are unlikely to be found in blood-iron, are removed via the addition of lime to the metal, which forms the slag on the surface of the metal. Other metals might float to the surface or sink to the bottom, or just find themselves alloyed into the iron. I would imagine that, especially in cities that use a Roman plumbing system, the lead content of blood-iron would be notably higher than that of regular iron.

I can't say much more than that. Any metallurgists happen to be on this forum?

[Reboot]

You get mineral iron from food and the body converts it to hemoglobin. So why not just extract the mineral iron from food in the first place, easier than changing proteins to iron.

I believe the point is less to get an entirely practical way of "mining" iron, and more "I FORGED THIS SWORD FROM THE BLOOD OF MY ENEMIES" symbolism for a tyrannical ruler.

[Jay R]

The chemical knowledge needed is far beyond what you could expect to know. Magic is easy and common. Science is hard and rare. So use your strengths. I recommend that you try to research an extract iron spell.

[Cluedrew]

To Jay R: From the perspective of a medieval person who is experimenting until something works: Is there a difference?

[Zaydos]

On that note the chemical knowledge is pretty basic alchemy.

[WarKitty]

Actually, this does hold up under my scrutiny (and I'm a chemist). Step 3 would be the most difficult part given the technology level. Iron oxide is insoluble in water whereas most other components of ash are soluble, so this would help. Thankfully, you don't need to get it to very high purity.

You might be better off using natural power sources than peasant power. Even medieval technology can take advantage of a waterfall, which could potentially generate quite a lot of pretty steady power.

[Xuc Xac]

Do keep in mind that many fantasy universes have divination magic available.

Magic that answers questions doesn't help if you don't know enough to ask the right question.

[RickAllison]

On the question of rounding of humans killed for it, we really need to consider the important questions. Which sounds better:

"The blood of a thousand foes created this sword. Cross me and your blood shall be the first of a new blade."

"666 souls gave this blade life. Decide now whether you would give yours to the devil as well."

[eru001]

On the question of rounding of humans killed for it, we really need to consider the important questions. Which sounds better:

"The blood of a thousand foes created this sword. Cross me and your blood shall be the first of a new blade."

"666 souls gave this blade life. Decide now whether you would give yours to the devil as well."

I like the first one


also, gotta go with the blood to ash to rinse to iron method. It checks out as far as I can tell for doability. as far as cetrafuge construction, a watermill (as were fairly common) and a good gear ratio are likely a better option.

[Strigon]

You would basically have to remove them the same way that impurities are removed from most metal samples. The sample is heated to a liquid state, and everything that boils or has a smoke point below that temperature vaporizes off. That handles most impurities. Silicates and similar, which are unlikely to be found in blood-iron, are removed via the addition of lime to the metal, which forms the slag on the surface of the metal. Other metals might float to the surface or sink to the bottom, or just find themselves alloyed into the iron. I would imagine that, especially in cities that use a Roman plumbing system, the lead content of blood-iron would be notably higher than that of regular iron.

I can't say much more than that. Any metallurgists happen to be on this forum?

Perhaps I'm missing something obvious. Wouldn't that get rid of all impurities below a certain boiling point? We were discussing identifying, and selectively retaining, beneficial impurities. How would you, for example, get rid of a harmful impurity that boils at 200 degrees without getting rid of a beneficial one that boils at 175?
This feels like one of those mathematical/logic puzzles that goes about on the internet, and I'm sure somebody's going to point out the glaringly obvious thing I'm missing.

I believe the point is less to get an entirely practical way of "mining" iron, and more "I FORGED THIS SWORD FROM THE BLOOD OF MY ENEMIES" symbolism for a tyrannical ruler.

Exactly. I mean, if you're willing to extract it from the food they ate, why not just go one step further and extract it from where the food gets it? That is, mine it the normal way.

''I FORGED THIS SWORD FROM THE BLOOD OF MY ENEMIES! ... Okay, well technically not, but it would have been in their blood, eventually. Probably. Some of it, at least. AND IN FORGING IT I HAVE DEPRIVED THEM OF VITAL NUTRIENTS; ITS MERE EXISTENCE WEAKENS MY FOES!''

[GorinichSerpant]

On the question of rounding of humans killed for it, we really need to consider the important questions. Which sounds better:

"The blood of a thousand foes created this sword. Cross me and your blood shall be the first of a new blade."

"666 souls gave this blade life. Decide now whether you would give yours to the devil as well."

Well the first includes more people and probably has more anguish for the souls that became trapped with their blood as they have become confusingly warped and twisted with a thousand other souls.

On a similar note, this process leaves a byproduct of ash right? Well why not let that good ash be used to make a sort of necromantic dust storm or sludge monster that screams in agony with a thousand spirits, bound to the dreaded bloodblade!

[bulbaquil]

On the question of rounding of humans killed for it, we really need to consider the important questions. Which sounds better:

"The blood of a thousand foes created this sword. Cross me and your blood shall be the first of a new blade."

"666 souls gave this blade life. Decide now whether you would give yours to the devil as well."

From a purely poetic standpoint, the first flows better and sounds more menacing, whether or not you emphasize "your" or "blood" more in the second sentence. While the number 666 is symbolic, the meter doesn't really work, especially as it's followed by a stressed monosyllabic (plus the two-stressed followed by at-least-two-unstressed pattern of "deCIDE NOW whether..."), and as such the second sounds more prosaic.

[Coidzor]

The chemical knowledge needed is far beyond what you could expect to know. Magic is easy and common. Science is hard and rare. So use your strengths. I recommend that you try to research an extract iron spell.

That is indeed something I've been considering, though the idea of thralls drudging in the blood vats fills me with a certain amusement, so I wanted to see what others might think of.