Bronze Sword Manufacture

I plucked this copy from the site of a craftsman who is making Bronze Age swords using the methods as best reconstructed. We learn something very important. It is that Bronze swords are and were superior to Iron Age swords for a thousand years or so. There was no good reason to switch except in terms of availability.

That means that a long accepted idea that the transition represented technical progress is rubbish. It represented nothing of the kind. What the transition represented was a dramatic loss of supply of top quality copper.

As I have already posted, the primary supply came by the end of the Bronze Age from the native copper mines of Lake Superior. Ample evidence supports mining activity there coincident with the thousand year history of the European Bronze Age that removed at least 5,000,000 pounds of copper. That suggests that the shipping rate toward the end perhaps approached several tons per year. That is volume that is completely believable for the time.

That it then reached Atlantis at the Straits of Gibraltar and was there alloyed with tin from Britain and forged into trade goods is mere mercantile sense. This also meant that all the shipping and skilled artisans concentrated there making it all completely vulnerable to the Hekla Tsunami in 1159 BCE. Not only the head but the arms and legs of this Bronze Age civilization was cleanly wiped out and unable to start over.

The copper supply from Lake Superior was unique inasmuch as it was in the form of native copper without the problem of sulphides and their related metals. It was also in the form of high grade ores which is unusual for copper. A typical grade would be around a hundred pounds to the ton. A good sulphide ore is usually around twenty pounds to the ton and includes iron and other base metals.

My conjecture is that the copper route was up the Hudson River to the Mohawk River and then transitioning over to the east end of Lake Ontario into the portage route through the Canadian Shield to Georgian Bay on Lake Huron. Archeological sites follow this route and include so called controversial sites in the Hudson Valley and a major site at Peterborough in Ontario.

Several tons of copper is well within the haulage capacity of a canoe based transport system.

The rest of the route would be directly to Isle de Royal in Lake Superior which was one of the major Bronze Age mining locales with hundreds of mining pits. I discuss this more extensively in my manuscript Paradigms Shift. I obviously need to add an addendum on the crucial role of the not so legendary Atlantis.

The original difficulty that everyone had with Plato’s tale of Atlantis was that no one could understand a reason for such a civilization to even exist. Egypt and Mesopotamia is obvious. The agricultural surpluses of the Atlantic coast were surely minimal and founded on cattle culture. This was not conducive to the building of Bronze Age cities.

That objection is clearly moot and Rainer Kuhne has shown us the actual location of the city itself. Once excavated, we will surely find plenty of evidence of the Bronze trade.

Apart from the design, the three qualities that you would look for in a bronze sword are, weight, balance and alloy, the level of skill Bronze age sword makers achieved with clay casting technology is stunning, and the fact that no one can match them today, is even more humbling.

WeightBronze swords rarely exceeded 800 grams, if it is over 1 kilo it is way to heavy "(it's a lemon"). Due to the difficulty of casting swords in sand, most foundries will cast on the heavy side, and although the end results would look good in a glass case, they bare no comparison to a genuine Bronze Age weapon.

BalanceIt is interesting that if you were to look at the balance point on bronze age swords, its much nearer the handle than you would expect, the blades taper evenly toward the point, and are not end heavy.

AlloyThe alloys used in the bronze age for swords, on average, vary from 8% to 12% tin and in later swords the lead content varies 1% to 5% depending on the tin content. My personal feelings are that the hardness of sword alloys could not exceed the hardness of the tools used in the process of edge hardening.All bronze age sword edges were hardened and sharpened at the same time, the edges were forged down to a thin, hard wafer. The work is so neat, its not easy to understand how they achieved it.

Over the past couple of years I have had some interesting interactions with archaeologists researching bronze swords. Subsequently I have come to the conclusion that we only see bronze swords in drawings in one dimension, and have little understanding of their weight, balance and how they were used.The first thing we would all say, when a bronze age sword was paced in are hands is, "it's so small", and they were small! It is only by the end of the bronze age that swords were getting any thing like the size we imagine, so 67cm would be a very big sword, and would probably weigh around 700 grams.

"What’s so good about, my swords?"

I hear you ask. I cast my swords vertically in very hot stone moulds. This means I can cast swords at the right weight, it also means I get a better structure to the bronze. As the casting method is nearer the bronze age method, I use a 12% tin/copper alloy which is at the top end for tin content for a bronze age sword. This casts well and gives a nice stiff blade. I mix all my own alloys and never use soft silicon bronzes.

Hardened Edges

One of the most beautiful things about the bronze age swords are the recasso edges, which are forged in. All my swords come with hardened edges, done in the (forged in) bronze age method. The forging is quite time consuming and I believe I am the only person able to do this at the moment. I cast all my blade as near to a sensible weight for bronze age sword as possible, and tuning a mould might take me many days and up to nine castings until I am happy.

In recent television programme for the BBC, one of my bronze swords was repeatedly stuck against a reproduction of an early iron sword, in a test to show the advantages of iron over bronze. Even though both myself and
Hector Cole (the iron sword maker) had advised the programme makers the that the bronze sword would do better than expected, they were very surprised. The bronze sword was more than a match for the iron, both blades received heavy damage. The ability of bronze to rapidly work harden under impact, and the lack of carbon in early iron swords must have created a bit of a technological stand off around 700bc. At this time the art of the bronze caster was at its height and iron working was in its infancy.

In my work as a bronze sword maker i try to catch the essence of sword making in the bronze age and get as close as possible to the originals.

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