How far could a society technologically advance without using iron?

Question

In my world, sapient beings cannot access iron for use in technology or anything else.

Iron does exist, in the same quantities as that on Earth, but no one can access it, so as general element composition is the same, including proportions of other metals. There is simply something stopping humans from mining it. Some sort of magical force prevents humans from collecting it.

This fantasy world has lots of magic, which would probably help with technological development quite a bit, but for this question, we can pretend it doesn't. In most other respects this world is mostly like Earth.

I want to know the limit of technological development in absence of use of iron, before I attempt to find a way around it.

Q: How far development of technologies can go, if we do not use Iron in the process?

Answer 1

The main thing about iron vs other materials is not about how much we need it, but how plentiful it is. It was actually a pretty hard metal to process all the way into the medieval period process because it takes a lot of heat which is the main reasons bronze was the preferred alloy for so long despite needing more exotic materials. But, if you take all the iron out of the ground, you need to replace it with something else. This could mean a lot more copper, tin, nickel, etc to work with. Bronze or brass could be used for nearly everything we used iron for leading all the way up to the modern era where everything that is currently made out of steel could be substituted with titanium, aluminum, tungsten, or copper nickel alloys, etc.

In reality, iron alloys are rarely the best metals to use for any given application, but we use them because they are cheap.

My guess is that it would not slow down the march of technology at all unless you were to replace it with something useless to the industrial revolution like silicon. In this case, there would not be any cheap, mass-producible metals to work with which would inhibit your ability to develop automobiles, rail-systems, etc. In this case, you would likely get stuck at a more-or-less medieval tech level until you can figure out a way to process aluminum (the other really abundant metal found near the Earth's surface).

If you go the other direction and completely replace iron with large amounts of other useful metals like copper, tin, zinc, nickle, etc. you might actually accelerate technology. The bronze age focused around a relatively small geographical area (The Eastern Mediterranean) since it was one of the only places on Earth where large amounts of copper and tin could be brought together. While Phoenician trade routes spanned all of Europe, the farther you moved from this central nexus, the more rare and expensive bronze would become meaning that many civilizations where held back from becoming more advanced by scarcity. This problem became even more pronounced around 1200BCE when the trade routes were ended by a devastating series of wars, and the whole of Europe was plunged into a major dark age. But, if tin and copper could be found pretty much everywhere like iron can be in our world, then the wars fought in the Aegean would have not been able to cause a ripple effect across all other civilizations. There would be no Bronze Age collapse, and no 1st Dark Age possibly causing your world's technology to progress an extra 1000 years ahead of schedule.

Answer 2

There is no real limit

Assuming that other metals are widely available, and other issues, like biochemistry and planetary magnetism are somehow solved, a civilization can advance without any hard limit. Let's also assume that iron is always available in small quantities and can be used when necessary as a "precious metal". However, there would be some hurdles to solve.

1. Iron age never comes

On Earth, iron eventually supplanted the use of many metals and alloys because or its abundance. However, if other metals, specifically copper, nickel and zinc are more abundant, alloys like bronze and brass can hold their own against iron and many early steels. As a result, bronze age would flourish all the way into industrial age. Metals would probably be more expensive than iron during antiquity and medieval epoch, but assuming that alternative elements are abundant on this planet, price difference would never be critical.

2. Industrial age delay

On Earth, one of the main factors which allowed transition to industrial age was the new way to make steel (and wrought iron) in huge quantities. Blast furnaces are very scalable and very doable at Renaissance tech level. On the other hand, there is no comparable way to jump up production of bronze, brass or other construction alloy at that tech point. Their production would increase, but only gradually.

3. Specialty steels are not available

While bronze and brass are superior to iron and crude steel, more advanced alloy steels are undisputed kings of mechanical world. Aluminum/duralumin, titanium and other metals can beat steel in one or two mechanical properties, but not across the board. In addition, aforementioned aluminum and titanium are "high hanging fruits" in technological tree, and I don't expect them to be available until later during the industrial age. Overall, the lack of specialty steels would delay many applications and progress in general.

4. Ferromagnetism and electricity

Virtually all electric motors and generators rely on ferromagnetic property of iron. Some other metals like nickel and cobalt are also ferromagnetic, but to a lesser degree. This factor may delay the widespread use of electricity.

Answer 3

There would be hurdles, but you should be able to achieve modern technology, just in a longer amount of time.

Without iron, your next-best replacement metal is most likely copper, meaning that everything we use iron or iron alloys for, would need to instead use copper or copper alloys.

Nails
Either your early nails would be copper or your woodworking would have to use joints to avoid needing metal. If the civilization chose joints over copper nails, that could foreseeably slow down the building of houses, etc. but wouldn't prevent expansion outright.

Amount of available materials
As @Nosajimiki, a big perspective to consider is, if you take all the iron away from Earth, do you replace it with something else, or make Earth a smaller planet? You could be nicer to the civilization by replacing all iron ore with copper ore, meaning there would not be a bottleneck of supply issues for mass production, or you could make it harder for your civilization by replacing it with silicon, rock, or just shrinking Earth's mass.

Rust
Iron oxidizes to produce rust, and copper and its alloys also oxidize. With copper oxidization, the layer is usually superficial and once formed prevents more oxidation. For purposes where oxidation is not acceptable even superficially, the civilization would need to resort to the same techniques used for iron: plating with zinc, or something else like tin.

Infrastructure
Skyscrapers and other large infrastructure rely on steel beams for strength, so the potential size of skyscrapers would probably be limited without iron. More material might also be needed to achieve the same strength, or your civilization might be filled with less rectangles and more arches and other shapes that provide more strength.

Mechanical Gears
Gears could be a sticking point - gears can be made out of bronze, but again it comes down to strength. I'm unsure of the specifics, but the civilization would need to be able to make gears out of a copper alloy that could handle an intense application like a car's transmission.

As long as you can build up your society's house with copper nails or joinery, go through the industrial revolution with copper alloy gears being able to replace steel gears, and infrastructure integrating more arches and other "hacks" to achieve strength rather than relying mostly on the strength of the metal beams, I see no reason the civilization couldn't reach modern technology - it would just take longer and possibly be more resource intensive and require more mining.

Answer 4

I don't think you ever achieve high technology.

Lot of technology is pretty dependent upon iron, esp. considering that technology is dependent upon previous layers of technology.

It is very abundant, about 90% of the metal mined per year is Iron - roughly 100 times as much iron as copper. And correspondingly cheap, and suitable for many structural and other roles. It has many key applications critical in developing modern technology. Don't ignore cheap as important, if things are too expensive, they don't get done. Can you imagine how expensive copper would be if iron was not an option?

Would magnetism have even been discovered without lodestones? Certainly iron is key in electric motors and generators (though modern rare-earth magnets are capable replacements)

Would farming ever have advanced without iron plows (bronze is just too soft), iron horseshoes as well as the shovel, pick, axe, hoe, hammer, etc. used.

All kinds of early and late machinery depend up iron components. For example, I doubt you could even make a useful surface plate without iron, I know that many machine tools would not be feasible without iron. You can't bootstrap high-tech without lathes, mills, drills, etc. needed to make precision equipment.

Internal combustion engines essentially require steel. Steam engines are not nearly as efficient or powerful.

Trains, automobiles, modern ships, etc. require steel.

High strength cables are used in more places than you would guess, steel is the only realistic choice for technological development. Bridges are very limited in comparison without steel and steel cables. No skyscrapers either.

Wire making in quantity requires steel.

Industrial chemistry require iron for a number of essential processes. Industrial scale refrigeration is key for many techs - that's gone too. Electric furnaces, gone and no, you can't replace these with non-electric furnaces in some applications.

Others have mentioned aluminum. You won't be making useful quantities with electric generators. Other advanced materials have similar problems in need for electricity, high powered machine tools, etc. that need iron/steel.

Oil drilling - not without steel. That kills many other essential technologies too.

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All surface plates were made of iron for about 150 years of history. Although modern surface plates are made of granite high end versions are still made from iron.

I did not say plows required iron, I said advanced farming plows required iron, e.g., industrial farming required iron based plows.

At the end of the age of steam, mid 1900s thermal efficiency for a steam engine was around 6%, but a diesel engine is typically around 35% efficient.

Answer 5

On Earthlike planet, it does not look too good:

Is there an alternate hard metal available in similar quantities?

Once you have figured out how to get the stuff out of ores, Iron is a very versatile material. It is hard. It forms all sort of delicious alloys with completely different properties. It is magnetic.
And above all IRON IS VERY COMMONLY AVAILABLE from ores. To the extent that about 5% of the ground you dig up can serve as an Iron ore.

Earth contains approx 800 billion tons of accessible, high-quality Iron ores. By comparison, there are about 680 million tonnes of copper ore. Yes, copper is 1/1200th as abundant as iron.

For a material to serve as foundation for a technological civilization, it needs to be:

1. Very commonly available in sufficient quantities.
2. Capable of being worked with the tech level of the civilization.
3. Have suitable physical properties. Specifically Hardness, and Durability.

Organics (Wood, Bone) can only go so far. They are plentiful and workable, but their physical properties are lacking. Ditto for simple mineral composites: Pottery, ceramics, glasses. (yes, ultra-tech glasses and ceramics are awesome. But not medieval to early industrial era, which is where Iron was the star)
So it has to be metal.
On Earth, the only metals that match the criteria are Copper, Iron, and Aluminium.

Unfortunately until one can access Aluminium, which is also very abundant and versatile but absolutely requires high technology to process, Copper and Iron are all you really have!
Copper and its alloys are perfectly suitable for early civilizations with their limited means and needs. However, scarcity is a problem.

If your world has an alternate strong metal that is similarly abundant to Iron, say for example hugely inflated amounts of copper ores, then progress will be almost unimpeded.
The only important role that will be absent are the ferromagnetic properties of Iron, and these can be substituted by Nickel, Cobalt, and others.

If your world contains similar elemental abundances to Earth, but no Iron is allowed, then your technology will stagnate at the late medieval to early Renaissance period.

While Copper and Bronze are perfectly fine materials for almost any application where one wants Iron or Steel, the scarcity of the material will not allow global civilization-wide adoption of metal tools and machines. This will enormously delay research progress, almost certainly delaying access to technology required to process Aluminium for so long that the world completely runs out of Copper.

Answer 6

High tech is achievable. (no magic required)

However, there are plenty of problems to solve, a good collection in Gary Walker's answer, on those it can be depicted how it's done differently, and presence of magic aka "free" energy definitely helps in that.

History of development may differ significantly, not necessarily the speed, however. Meaning it not necessarily adds another thousand years between a steam engine and an iphone29, but may or may not add a hundred years.

Some solutions may not look like we know them today, railroads mentioned in comments as an example, but there are other variations of those. So as honorable mentioning of the current state of usa transportation system, as an example of good roads system and weak railroad system, or more ancient times developed road system in Rome empire, water channels of medieval time so as of today, maglev, and low tech exotics from '50-'70s, airships.

All sorts of inefficiencies of alternatives, when we compare it with modern solutions, are not stoping factors for development, again an honorable mentioning is steam engines of a steam-era when they were 5-10 percent efficiency at their relatively mature state which is few times less efficient than any combustion engine of today. And that inefficient solution did manage to propel us through an industrial era of the development of our technologies just fine. And when u do not have alternatives, as of today's example no unobtanium which is 50 times stronger than iron, one will use that solution just fine.

Fundamentals and differences

Fundamentals of our technological development weren't the iron and iron age by itself, but discovering\development of means to convert energy to mechanical work to amplify our strength(free labor force), so as energy sources to produce that energy as wind-hydro-wood-coal-oil. people were quite happy burning wood for energy production, but yeah it grows too slow, and then eureka moment - we have coal, a lot of it, let's burn it, and then comes oil and it even easier to burn especially in specific applications.

So a question to be answered can be means of energy conversion be build without iron. The answer is yes, windmills were mostly woods - wooden gears, wooden shafts etc.

First steam engine application for industrial purposes, not sure they used iron at all, for main components, someone more curious may add it here.

Another question to address is the scalability of solutions. iron has certain advantages, and no it isn't its abundance which is helpful but not the main factor, but that iron is a strong metal and it isn't brittle it has plenty of alloys etc. And that strong metal can be relatively easily machinable - u can cut it, u can grind it, so as u can cast it, etc.

This set of advantages in one package is hard to beat, so overcoming should be done with different materials and in different ways depending on application demands.

Despite those hurdles, industrial steam era applications (mean up to ends of the steam era) replacements are relatively easy in many cases.

Alternatives

• let's illustrate some of the possible alternatives

Steam era

At the start efficiency of engines was close to zero, it just worked, but down the road, it got better and took the shape of the engines we may depict in our mind as soon as we hear words steam engine. But it started like:

A newspaper in March 1702 announced that Savery's pumps were ready for use and might be seen on Wednesday and Saturday afternoons at his workhouse in Salisbury Court, London, over against the Old Playhouse.

Mind u, 17xx, no moving parts at all. So as this comparison is quite interesting even if not that reliable wiki/Thomas Savery

The Savery steam pump was much lower in capital cost than the Newcomen steam engine, with a 2 to 4 horsepower Savery pump costing from 150-200 GBP.[18] It was also available in small sizes, down to one horsepower. Newcomen steam engines were larger and much more expensive. The larger size was due to the fact that piston steam engines became very inefficient in small sizes, at least until around 1900 when 2 horsepower piston engines were available. Savery type pumps continued to be produced well into the late 18th century.

so it about 200 years of development until it was full steam, quite a time to wrap the brain around different alternative solutions.

alternatives, stone

u may laugh, but the stone is a decent alternative, not every stone but some basalt and diabase, in stationary cases even a good alternative to make a steam engine, with pistons and all that, for engine blocks, for valves.

And here is not so well known technology, basalt and diabase casting. Here is some marketing advertisement from the link

Basalt casting was originally developed in the Czech Republic to be used as a replacement for iron and steel which was in short supply after WWII – the crushed natural basalt is heated back to molten lava and then poured into moulds to make components such as pipes and floor tiles, which are incredibly hard wearing and abrasion resistant

originally developed by czech's is a marketing, it was started in a good old place where all good stuff comes from revolutions and fashion - by french in 18xx if i'm not mistaken, google brings plenty of links by keywords "basalt casting". in early 19xx some people toyed with the ideas of replacing iron with basalt and diabase casting, but it ended mostly on the primitive side of things pipes where abrasion factor and chemical resistance are important factors, different slabs - this technology still alive.

But for early steam the abrasion resistance is a good thing, there are no combustion explosions in a steam engine, there will be no corrosion, almost the same tensile strength with half the mass as cast iron, rocks are abundant enough. So your typical factory steam engine or its marine counterparts can be made out of those casts. there are specific nuances and problems, but no without advantages.

Cast iron in most cases, especially simple alloys, most basic stuff is similar in properties with those possible stone castings, except thermal conductivity. And there are limited thermal cycles on a stone block, so u may invent 3 shifts working earlier, or keep it idle under minimal power over nigth.

pipes

Copper was used as an alternative for pipes under pressure - an advanced example of that is a car Doble Model E, some can see it in here as an example 1925 Doble E-20 Steam Car - Jay Leno's Garage nice piece of engineering, which uses copper pipes as its boiler, and 58bar pressure which is way more than early steam engines can handle.

for mobile applications replacing iron in boilers can be a bit challenging, but for stationary not impossible with mortar and stone may do the job, the main problem here is a poor thermal conductivity of stone, which is good for a shell and bad heat exchange, so even if u put stone pipes inside the boiler, as it was done with steam locomotives, it will be less responsible on changing the power until u improve on that, and Doble Model E is a showcase how it is can be done and that it may be as responsible as your typical car.

shafts and gears

it is pity that nobody mentioned composite materials as some of the replacements. But with stone, it is one of the ways to overcome one of its disadvantages namely brittleness of it. Chemistry in times of stem engines was on its rise in 18-19xx, and at the beginning of 19hundreds, there was already a good variety of plastics available. So as making glass fiber. And those were used for gears, bearings (friction bearings) etc.

composite materials are not only your typical fiberglass, metal + fiber also a composite material, metal metal etc. it all needs their own development, and coincidently they are all about replacing metals|iron improving its qualities, and compared to our history in the environment of inaccessibility of iron all that development will start early on and it will bring its fruits early, as simple cases are simple and what one needs is mostly incentive, which we got when "iron" become not good enough.

gear boxes - there are more than two alternatives for making gearboxes - different hydraulic solutions(more than one), different variable speed solutions which can be done out of plywood for machines at 1-2-3kw power, different belt solutions, hydraulic transmissions etc - there are solutions which can avoid problems of lack of strength in gear teeth or brittleness of them by not using them. For lower power solutions plastic gears, composite gears, aluminum gears, etc work fine.

Energy, after steam.

what caught my attention in Gary Walker's answer is the oil extraction problem, it begins to be a problem at times when high-density power sources are in demand, and it comes at a time of more advanced technology.

So as chemistry vessels and high-pressure vessels for mass chemistry production, which again is a sign of more advanced technology and so as more advanced technological competencies to solve those problems.

So as agriculture plows etc will need solutions.

As space rockets - there are different solutions to approach the problem of high volume high-stress vessels - that are different composite materials, aluminum alloys. So as with other space technologies to solve corrosion resistance, heat resistance - and iron isn't used that much(exclude engine) - so space technologies is our top-notch benchmark for some cases and it sort of shows to us iron isn't a winner here.

however, a transition from steam to that, in which combustion engines played their role, may come in a different way, maybe even somewhat skipping it. The same way as electric-powered cars didn't fly in 1900's, because of the convenience of alternatives of combustion engines, so as Doble Model E died for the same reason. in case of the absence of iron - electric powered solutions are the convenience and Doble Model E fights not internal combustion engines but electric-powered vehicles and probably wins over at some applications.

u probably won't see those high powered airplane engines of wwii, sea ships engines as those low rpm monsters will also have certain problems.

So there will be a plethora of problems, but it does not differ that much in the complexity of problems we solved to get us where we are today.

A characteristical difference maybe that u may work with less powerful or less compact solutions, jump additional hops be more creative, which will take its toll but not impossible.

• in time of wwii there were ship hulls made out of cement
• helicopters maybe not a thing, but airships may still be a thing (airships can be quite efficient, better than trucks, and a 1.5 times worse than railroads)
• precise manufacturing won't suffer that much, but there can be certain limitations on a big size, which is not that critical for making semiconductors as an example.
• big big machines monster trucks, excavators - pretty much kiss it goodbye, until u set a firm food at composition material and nanocarbon.
• jet engines, fighter jets, etc, probably arrivederci too.
• turbines do not necessarily suffer the same fate, but it needs a redesign.
• rotary combustion engines may be more popular than as of today
• fiber optics and a broadband connection - no problems
• electricity generation - doable but less efficient, preferably direct mechanical energy usage where it is possible (in production, as the backbone of tech development it is possible almost everywhere)
• springs will have a hard time and they are used a lot, but in some cases, there are alternatives(pneumatics as an example) in others u may need to avoid them by means of design and find other alternatives (chemically tampered glass, Compliant mechanis)
• cutting tools - more synthetic diamonds will do, I think it worth the change, lol
• bearings - more friction bearings, hydrodynamic bearings, hydro and aerostatic bearings, ceramic bearings which in many cases just are a better alternative to your typical one.
• structure elements more plastic, more aluminum, more composite materials.
• connections more glue use and epoxy and adhesives
• higher focus on chemistry
• firearms will have a problem, particularly powerful and rapid-fire ones. However, there are rifles with composite barrels.
• etc

where it is a problem in need to solve it will be solved directly or by going around. some technologies which didn't fly in our tech tree can fly in an iron-absent tech tree, some solutions can meet its nerfing, some won't fly.

the key technology of today - microelectronics and all the electronics can be achieved and be not affected that much.

Things that will be harder

• resource gathering, large scale mining operations will be harder
• deep hard to get oil extraction
• high tech wars
• getting down to 3% population in the agrocultural sector will be hard

remarks

• if u can improve upon of brittleness of stone and limited heat cooling cycles which is the same problem, then it can be used everywhere where cast iron was and is used.

• in absence of an alternative it pointless to refer to economic incentives as we see them today, as we do have options, but they don't - it is done or doesn't. And expenses are defined by widespread technology - the meaning amount of supply, amount of energy put in the refinement of technologies. Ceramic bearings are exotics to us, but for them, it can be a get-go from the very start when they needed them with decades of refinement of technologies and establishing production chains and capacities.

• ferromagnetic materials can be a problem for electric engines, so as generators - but it is not one which can't be solved by an excess of wires, so it is not a fundamental one. So as nickel and cobalt will play a more significant role where u have to have them. one does not have to have those metals more, u just use them less and only in places where they bring u the most, power plants as an example.

okay, those are my two cents on the topic