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A 3K-year-old copper smelting site could be key to understanding origins of iron

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Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#41

Post by GreenWatermelon »

card_zero wrote: post #12
lukan wrote: post #7

Earlier quoted context omitted.

"they just had a theory that copper processing lead to discoveries in iron processing." Is there any theory how it could have been any different? It sounds obvious, that advances in metal working comes from those working with metals and not from carpet makers.

They found ancient inhabitants of Georgia using iron ore as flux for copper smelting, so it's a theory of how they went from one to the other. It's not terribly exciting but it beats "they tried smelting rocks at random to see if anything good would happen".

Smelting random rocks (with fairly distinct appearances) sounds like a very logical thing to do. I would say it's a natural human impulse to experiment with random stuff and see what happens, that's curiosity.

What sound highly improbable is someone having access to this obviously different ore (used as a flux) but never thinking of smelting it.

Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#42

Post by bombcar »

GreenWatermelon wrote: post #39
Terr_ wrote: post #2

> Sparkly hematite mineral was used as a flux by copper smelters. Its distinctive appearance may have helped to attract attention from ancient miners and prospectors. Every once in a while I pull up some Wikipedia article with idle curiosity of "If I were transported back in time, could I usefully help this get invented?" One result of this is a helpless appreciation for how complicated it can be to even identify wha…

One of the axioms I go by is that people were never stupid. Our ancestors 5000 and 10000 years ago were just as smart , intelligent and curios as we are today. With regards to metals, I have no doubt someone, be it a kid apprentice or a master smelter, experimented with melting different rocks to see what comes out. After all, if you already know that different rocks spew out different metals (copper, tin, etc..) it…

"That old Copper++ is worthless, you need to try this Rust"

Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#43

Post by bluGill »

ReptileMan wrote: post #31

Can anyone explain iron - unless it is steel (which was not a common knowledge trough history) it is worse than bronze in every aspect. So what lead to the iron age?

The early processes for smelting iron resulted in a little steel which would be easy to collect and save for one big work. Over thousands of years you learn more and more of how to 'encourage this'

Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#44

Post by arnsholt »

chrisco255 wrote: post #36
ReptileMan wrote: post #31

Can anyone explain iron - unless it is steel (which was not a common knowledge trough history) it is worse than bronze in every aspect. So what lead to the iron age?

Tin was hard to come by in those days and necessary for bronze. Late bronze age led to civilizational collapse and trade networks that distributed tin broke down. Iron was more abundant and could be more useful by itself than copper alone. May have been used for farm implements at first.

To expand on "tin was hard to come by", I believe two major sources of tin have been identified for bronze used in the Fertile Crescent: one in Cornwall, and one in Afghanistan. They had to travel really far abroad to make this stuff.

Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#45

Post by WillAdams »

OJFord wrote: post #18

Can anyone recommend a book (I'm imagining sort of 'coffee table' style picture book, but not necessarily) on technological advancements through human history, ideally roughly chronologically but more organised around what needed to happen before the next was possible?

A broad overview, and kid-friendly, there is: https://www.goodreads.com/book/show/6314442-robert-crowther-... which is just what it says on the cover --- a tour through a house showing when things were invented.

A lot more focused there is: https://goodreads.com/book/show/35068671-the-perfectionists (but it's a rather dry text and quite periodic and focused on specific technologies)

Perhaps:

https://www.goodreads.com/book/show/48815394-1-000-invention...

There's a site which has come up here a couple of times along these lines which I'm not finding, but Britannica has:

https://www.britannica.com/story/history-of-technology-timel...

Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#46

Post by lightedman »

jandrewrogers wrote: post #3
Terr_ wrote: post #2

> Sparkly hematite mineral was used as a flux by copper smelters. Its distinctive appearance may have helped to attract attention from ancient miners and prospectors. Every once in a while I pull up some Wikipedia article with idle curiosity of "If I were transported back in time, could I usefully help this get invented?" One result of this is a helpless appreciation for how complicated it can be to even identify wha…

Absolutely. As luck would have it, many epithermal mineral deposits have both sparkly hematite and copper ore in the same structure. This is a well-known motif in mineral exploration. They show up in the same geography but are separated into different layers. You can find many papers on the structure of these ore bodies. These are known as supergene deposits[0]. The most important features of these deposits is that t…

"Amazing hematite crystals mixed with copper with strong assay signs of gold underneath."

Did you actually assay out anomalous gold concentrations or are you seeing the sulfides and oxides that are associated with gold? If the former, what sort of concentration are you getting?

Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#47

Post by card_zero »

GreenWatermelon wrote: post #39
Terr_ wrote: post #2

> Sparkly hematite mineral was used as a flux by copper smelters. Its distinctive appearance may have helped to attract attention from ancient miners and prospectors. Every once in a while I pull up some Wikipedia article with idle curiosity of "If I were transported back in time, could I usefully help this get invented?" One result of this is a helpless appreciation for how complicated it can be to even identify wha…

One of the axioms I go by is that people were never stupid. Our ancestors 5000 and 10000 years ago were just as smart , intelligent and curios as we are today. With regards to metals, I have no doubt someone, be it a kid apprentice or a master smelter, experimented with melting different rocks to see what comes out. After all, if you already know that different rocks spew out different metals (copper, tin, etc..) it…

Ideas improve over time. So people in the past have worse ideas. This might include fear of change, and some mythological notion of an eternal golden way of life, which you must dutifully maintain by spending a thousand years not inventing pottery, and if anybody dares to try it, beating them up.

Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#48

Post by IAmBroom »

pjc50 wrote: post #29
jandrewrogers wrote: post #3

Earlier quoted context omitted.

Absolutely. As luck would have it, many epithermal mineral deposits have both sparkly hematite and copper ore in the same structure. This is a well-known motif in mineral exploration. They show up in the same geography but are separated into different layers. You can find many papers on the structure of these ore bodies. These are known as supergene deposits[0]. The most important features of these deposits is that t…

This is similar to the "rare earth tailings" phenomenon, isn't it. A mine is built to extract one metal, the most profitable at that time, and everything else unextracted ends up in mine tailings or refinery slag. But, in addition to truly worthless silicates, that "waste" includes a bunch of other metals at low purity which may eventually be economic to extract.

Leadville Colorado was the site of a very minor gold rush, that mostly produced large piles of lead tailings.

Until someone noticed the lead tailings were not lead, but oxidized silver.

Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#49

Post by Sharlin »

GreenWatermelon wrote: post #39
Terr_ wrote: post #2

> Sparkly hematite mineral was used as a flux by copper smelters. Its distinctive appearance may have helped to attract attention from ancient miners and prospectors. Every once in a while I pull up some Wikipedia article with idle curiosity of "If I were transported back in time, could I usefully help this get invented?" One result of this is a helpless appreciation for how complicated it can be to even identify wha…

One of the axioms I go by is that people were never stupid. Our ancestors 5000 and 10000 years ago were just as smart , intelligent and curios as we are today. With regards to metals, I have no doubt someone, be it a kid apprentice or a master smelter, experimented with melting different rocks to see what comes out. After all, if you already know that different rocks spew out different metals (copper, tin, etc..) it…

> Then someone will give that mee Iron sword/knife/axe a try , duel a friend, ruin their bronze weapon, and said friend will be like "holy shit I want an iron sword too it's way too good" and bam you got a meme.

Iron is not a superior material to bronze, if anything it's inferior. Iron's either soft or brittle, depending on carbon content, neither of them awesome qualities in a tool or a weapon. Also, iron's considerably more difficult to smelt, and fully melting iron was not possible at the temperatures achievable with Bronze Age technology. Even after you learned that you need to use charcoal and very high temperatures to reduce iron ore, what you got was a spongy mass of very impure iron at the bottom of your furnace that you then had to refine further.

The biggest thing that iron had going for it was logistics. Where there was copper, there was no tin, and vice versa. Sourcing tin required trade routes thousands of kilometers long – no doubt the demand for tin was a large boon to long-distance trade across Europe and Asia, but it made bronze an expensive commodity.

It required new furnace technologies and a millennium worth of experimentation to perfect the art of controlling the carbon content (and what we now know is the crystal structure) of iron-carbon alloys precisely enough to make steel, and in particular steel blades that combine a hard (martensitic) edge and a flexible (austenitic) spine.

(For the record, Dwarf Fortress (unsurprisingly) is one of the few games that get this mostly right.)

Re: A 3K-year-old copper smelting site could be key to understanding origins of iron

#50

Post by jonathaneunice »

vanderZwan wrote: post #35

> These discoveries give weight to a long-discussed theory that iron was invented by copper smelters. Not to be flippant but who else could reasonably be expected to have invented it? Or is the implication that there were metalworkers at the time who weren't also copper smelters?

Right?

"Early metallurgists found to have been experimenting with the properties of metals and ores, laying the foundation for future advances that would prove economically and technologically important" is not the biggest possible reveal.

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