The Ancient Sword Of Goujian

Jan 2015
2,843
MD, USA
#21
I certainly agree that logistics and availability of materials will dictate what metals get used! To a large extent, at least. Yes, bronze has a lot of advantages over iron in terms of hardness and the ability to be cast. I'm *not* sure about the use of fuel for forging versus casting, there has been some discussion about that, but yes, even if you need a LOT more fuel for working iron than for casting bronze, if you have a lot of iron and a lot of fuel it still makes more sense.

The higher temperatures needed to *cast* iron were irrelevant (at least in the West!) because they didn't bother trying to melt and cast iron. For them, forging simple iron spearheads was a lot faster than laboriously making molds to cast bronze bronze spearheads, and came with a much lower failure rate. And I think I've heard people talking about the Chinese using cast iron weapons, but I honestly don't track anything about China--if they did, cool, it's certainly a point of difference between them and the West.

It should be noted that the use of bronze INcreased in the West during the Iron Age. There was just more of everything all around. So it wasn't a matter of a shortage of copper or tin, just that iron made more sense in the larger scale. Not to mention that the whole "collapse" thing is way overblown, but that's a different discussion.

Matthew
 

Dan Howard

Ad Honorem
Aug 2014
4,016
Australia
#22
That's not how casting works. You can't reuse the same mold over and over. The mold gets broken when the object is removed so you need someone making fifty thousand molds for those halberds. The casting failure rate will be a minimum of 5% so you really need closer to fifty three thousand molds. When your halberd is removed from the mold it takes considerable work to file off the tailings and clean it up. Then the edge needs to be work hardened with a hammer and some of these will crack during the process. Even without polishing and the replacement of failed attempts, it takes half a day's work to make a single halberd from bronze.

The same thing can be made in 30 minutes from an iron billet; even less if the billet has been preshaped into a blank.
 
Last edited:
Jan 2016
570
United States, MO
#23
A couple quick points to provide some context of the situation

1) China had cast iron since the 5th century BC, they used it for ploughs and belt hooks because it was too brittle to be a useful weapon. In fact some of the earliest iron in china that in not from meteors is cast and comes from the state of Wuyue on the pacific coast which implies a domestic origin.

Also, I recently asked an Professor Nick Vogt who studies Early Zhou bronze works about the potential import of bronze casting into the Yellow River floodplain from Central Asia and he stated that we don’t have solid evidence of casting techniques being transmitted. Furthermore we can see that a particular style of bronze casting radiated out from the Yellow River which implies a domestic origin. On top if this we have what appears to be another completely independent bronze casting culture in Sanxingdui. So, I am skeptical of claims of metallurgy being imported.

2) Late Chinese bronze swords were made of multiple allows cast onto each other. A core or spine of the blade would be cast of bronze with an 11% tin alloy and then the core would be put in a seperate mold and edges would be cast onto the core. The edges alloy varies from 18-20% tin this allows for a much sharper edge than lower tin alloys especially if no work hardening is done. After casting both the spine and edges of the blade, a third or sometimes fourth cast would be done to cast a handle onto the tang. This composite alloy casting would delay the transition to iron even though many warring states states used iron. And the early Han dynasty saw the use of cleanly laminated steel.

3) The rites of Zhou, a text which dates to the 9th century BC contains a section which is the world’s earliest treatise on metallurgy. The ratio of six different copper-tin alloys are listed and their uses are described. Now these ratios do not actually reflect the variation that we see in artifacts, but the text clearly demonstrates a sophisticated understanding of how bronze alloys work.

4) The terracotta warrior pits are invaluable for many reasons, but we can’t just take them to completely represent an army of the time. For one, much of the tomb, excluding the inner chambers has been looted. Also, certain bronze weapons in the tomb are not functional at all, but serve to stand in for iron ones.

I will write another post later and go into more detail.
 
Oct 2013
6,078
Planet Nine, Oregon
#24
Interesting! Thanks Keen Edge. In the Iliad, iron is used for domestic implements, ploughs etc. And bronze was the material mentioned for weapons too...
 

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