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Vic Froelicher's avatar

“Iron” refers both to a fundamental chemical element — the metal that built our infrastructure — and to a vital mineral for biological organisms. In metal form, it enables construction, tools and machinery; in biological form, it underpins oxygen transport, energy metabolism, and many crucial cellular functions. Good old Fe

This was one of your best!!

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Tomas Pueyo's avatar

Thanks! Super nerdy but I love it

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Iustin Pop's avatar

Very, very interesting. I didn't realise the Bronze Age lasted for roughly 2K years before Iron came on the scene.

Maybe AI will make it cheap enough to be able to feed bronze-age stories into it so that I can watch a documentary about that era, as the movie studios don't seem to go anywhere beyond Troy, I think.

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Umang Varma's avatar

You can find numerous short documentaries about the bronze age on youtube. Lots of great history on YT.

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Iustin Pop's avatar

Thanks, will look it up. But I also would like cinematic options, not sure why the earliest era the movies target is Troy, as written, and not the empires beforehand (2000-3000 BC).

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Tomas Pueyo's avatar

I hadn’t thought about this. You’re right.

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Julia D.'s avatar

I agree! There are several (though not as many as I'd like) good books set in the Bronze age and even before that. I'd love to see these favorites of mine in film someday:

Hittite Warrior by Joanne Williamson (1200 BC) https://a.co/d/8f8LIeG

The Egyptian by Walter Mikari (1386-1293 BC) https://a.co/d/96tHYUC

The Red Tent by Anita Diamant (1800 BC) https://a.co/d/0sRb3RI

Winter on the Plain of Ghosts by Eileen Kernaghan (2000 BC) https://a.co/d/fWQxN4J

Reindeer Moon by Elizabeth Marshall Thomas (18,000 BC) https://a.co/d/df7z5Fl

Shaman by Kim Stanley Robinson (28,000 BC) https://a.co/d/18DsSfa

The Clan of the Cave Bear by Jean M. Auel (33,000 BC) https://a.co/d/3JT4hQq

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Iustin Pop's avatar

Much appreciated, thanks!

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Eduard's avatar

You said it yourself - I think screenwriters don’t go back before written history as it is much harder to assess what is historically ‘correct’. So yeah you could make a movie set in the stone age but the story line would be less appealing for A) it will be regarded as less historically correct and B) because people don’t recognize the story culturally (been told the story before through (informal) education). Would be an interesting watch though - and you could ask AI to make multiple versions which could create more interest and so research into that time period

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Al Christie's avatar

It may be true that the bronze "Age" was before the use of iron was as widespread, but iron and how to smelt it was known very early.

"Lamech’s other wife, Zillah, gave birth to a son named Tubal-cain. He became an expert in forging tools of bronze and iron..." Genesis 4:22

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Thomas Blaudeck's avatar

Great reading, Tomas. Allow an ad-commentary: Interestingly, group-11 metals were the first ones to be brought into the form of thin patterned nanolayers following inkjet printing of metal-organic molecules and the thermally or photonically induced decomposition, yet in the series Ag-Au-Cu. I gave a plenary talk at MRS Fall Meeting 2010 in Boston on that, see also our monography Inkjet Printing of Group-11 Metal Structures (2015)

https://www.researchgate.net/publication/310843211_Inkjet_Printing_of_Group-11_Metal_Structures

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Tomas Pueyo's avatar

I started going down the rabbit hole of the physics behind Group 11’s properties, but when the different types of layers of electrons started piling up, I stopped. My Materials Engineering university professors would be ashamed.

What you say can’t be a coincidence. Why?

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Thomas Blaudeck's avatar

For an estimate on chemical reactivity, it is often sufficient to look at the outer electron configuration which is similar for elements adjacent in one group. Au, Ag, Cu can be stabilized in metal organic frameworks adaptable to liquids. Upon processing, these organics can be 'cleaved' and furnaced away and then 'magical' Ostwald ripening is in place the way to bring them to layers, alike they sweat out on the quartz inside the mountains.

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JBjb4321's avatar

Nice! History repeating, and all driven by the geometry of electron orbitals. In the same vein I find it cool that Si was a strategic trade in late paleolithic (see my above comment on flintstone trade), and came back big time with cement/concrete (which basically replaces C with Si), and now of course with semi-conductors - where we replace the C in leaves by Si solar cells, and the C in our brains by Si microchips.

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Tomas Pueyo's avatar

Sounds like you’re drafting a UT article on Si!

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JBjb4321's avatar

There sure is much to say about it. It's one of the big 4 of the crusts elements, but it had to go through C biology to get to complexity. Either C or Si, they're the swings states - can give or take e-, be conductor but not quite, so they end up ruling, it's like politics. O is too predictable, always taking e-, and the alcalines too predictable in giving them. The swingers introduce the complexity in the universe.

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Thomas Blaudeck's avatar

Natural vs artificial brain: We have to be aware that both C and Si are substrate only, all major functions (i. e. signal transport, communication) come from traces of electrolyte ions, amino acids, or dopants.

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JBjb4321's avatar

Good point! One may argue that C / Si provide structure (rather than just substrate). But the dopants etc. with rare orbitals are where the gradients/curvature allow the cool chemistry to happen - very nice and a more accommodating vision of silicon/carbon society where the weirdos and misfits transform it into something more interesting than, say, a diamond...

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JBjb4321's avatar

Beautiful stuff, thanks a bunch Tomas. On your last comment - our overfocus on the industrial revolution as the single bend in the curve is typical of a civilisation's navel gazing. Well, it's not only myopia, the exponential being self-similar in scale, you will always find the "bend" near where you look, pretty much.

Talking of which, I find another story at least as fascinating as that of the early metals is that of the paleolithic international trade networks, where people transported quality flintstone or obsidian thousands of kms, including by sea! Yeap, those hunter gatherers were not that different from us.

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Tomas Pueyo's avatar

I have an article on the Industrial Revolution before the Industrial Revolution that I think is super cool. Hopefully next year!

I had no idea about international Paleolithic trade of flintstone or obsidian. Is there any good post on this?

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JBjb4321's avatar

No, unfortunately the info is there but scattered across academic publications and big books. UT would be the first one ! I would like a sequel to the quest for fire where Naoh now goes to sell some flintstone across the mediterranean...

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Steve Mudge's avatar

Great history!

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Jojo's avatar

Amazing! This will be very helpful after the coming apocalypse!

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Weston Parker's avatar

Wonderful and interesting as I just invested in silver.

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Al Christie's avatar

Great piece - fascinating. I'll add that gold is the first metal mentioned in the bible - right in the 2nd chapter of Genesis, which adds detail to the creation account of the 1st chapter. Check Gen.2:11-12 - the land of Havilah, "where there is gold...the gold of that land is good".

Then in Gen.4:22, it says Tubal-cain, the son of Zillah, wife of Lamech, was "the forger of all instruments of bronze and iron". This was very early.

Taking the bible literally, and simply adding the ages from the birth of one patriarch to the next, Lamech, the father of Noah, was born 874 years after Adam was created, (so Adam, who lived 930 years, was still alive) and lived 777 years. When the patriarchs lived such long ages, it's not hard to imagine that they had plenty of time and experience to learn how to mine and smelt metals.

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Tomas Pueyo's avatar

I didn’t know!

In light of this post, it makes sense: it was not the first of many. It was the first of very few!

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Alessio Quaglino's avatar

Great post! Is that last chart linear in log scale?

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Qiulin Wu's avatar

with copper, frac of weight:

1/6 Tin for Big Bell, Tripod cauldron

1/5 Tin for Axe, knife

1/4 Tin for sword, spear

1/3 Tin for Axe

2/5 Tin for Spear head

1/3 Tin for mirror, flint

Yes mirror, people still use metal mirror 1000 years ago.

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Peter Tillman's avatar

Nitpick re footnote 3: copper is about 46% as dense as gold: 8.96 vs 19.32 gms/cc. Doesn't really sound right to say copper is 115% lighter than gold..... though it is 2.16 times denser.

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Daniel B's avatar

If you define "lightness" as the inverse of density, then the numbers work out.

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Al Christie's avatar

Tomas, I just came across an article that is right up your alley - by Amanda van Dike - 'Amanda's Substack'. She's an expert on mining and minerals. Here's an excerpt. Note the reference to geography:

"This is the central irony of the sanctions regime. By severing Russia from Western markets without neutralising its productive capacity, the West has effectively subsidised its chief strategic rival. Unlike greenfield mining projects elsewhere—where new supply requires decades of permitting, billions in capital, and fragile social licence—Russia already possesses the infrastructure, technical expertise, and industrial heritage needed to bring new minerals to market in a fraction of the time required elsewhere in the world.

That capacity rests on geography first and foremost.

Russia is the largest country on Earth, covering approximately 17.1 million square kilometres of land and inland water—placing it in a category of its own. The next five largest countries—Canada, the United States, China, Brazil, and Australia—cluster between 7.7 and 10 million square kilometres. Russia is around 70–80% larger than any of them individually.

This comparison matters because it is not arbitrary. Its not a coincidence that these same countries also constitute the world’s leading mining nations by production value, reserve base, and strategic mineral breadth. Size underpins geological diversity, reserve depth, and the ability to host multiple world-scale mining provinces simultaneously. Russia does not simply sit among these peers—it dwarfs them.

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Akash Jaggia's avatar

Amazing stuff as always. Just to let you know there is a typo in the paragraph under the image of iron vs steel about the discovery of copper!

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Eduard's avatar

More of the nerdy subjects please. Crossovers between beta subjects such as chemistry and geopolitics, history and economy are so interesting but undervalued and overlooked imo. Keep up the good work!

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Michael Magoon's avatar

Great article. The specific characteristics of metals played a huge role in human history.

I would like to correct two minors points:

1) During the Bronze age farmers rarely used bronze tools. It was simply too expensive. Its use was concentrated in weapons, tools for specialists, ritual objects, and elite prestige goods. Most ordinary people continued to rely on stone, bone, wood, and simple copper for daily life. Bronze was expensive, scarce, and tightly controlled in most early states.

2) Regarding the graphic at the bottom: GDP and technological innovation are two different things. As you correctly state, technological innovation is part of human history and it goes back at least 300,000 years. Increased material standards of living (shown in the graph) are much more recent.

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Sonja Davie's avatar

What you're essentially saying here is that civilisation led to more exploitation, more inequality and more violence. This is not a good thing, as per this article

https://www.theguardian.com/environment/2025/aug/02/self-termination-history-and-future-of-societal-collapse?CMP=Share_AndroidApp_Other

Also, the demand for wood before it was replaced by coal for generating heat meant there was less deforestation than subsequently. Wood was a valuable resource so it was protected by landholders who effectively farmed it and sold it off selectively for a profit.

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Michael Magoon's avatar

LOL

Totally twisting his argument, so you can post a link to your own article about a completely different topic…

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