Tins for the memory
Just an authorial note
I feel a bit awkward about Thule Bronze, since initially I opposed the notion strongly. I also opposed the acquisition of Norse Iron. My feeling was that actually making a persuasive case for a hypothetical Thule Agricultural complex capable of supporting a reasonable population density and a relatively complex civilization was quite enough. The Thule were a modern era dawn civilization.
Having them develop or acquire metal, that seemed like a bit too much, too soon.
I was compelled to change my views.
Basically, the issue is the existence of a live copper culture along the Coppermine river, and as pesterfield has pointed out, along the Copper river. We can only know for sure that there were mature copper cultures here at the time of European contact - say the 18th century. But they were mature copper cultures. There was a sophisticated assortment of copper tools, and there was limited trade or exchange beyond the borders of the river basins.
As I’ve said, we can’t know how far back this copper culture goes. Conceivably, it might precede the Thule themselves, originating with the Dorset or earlier. Or it might be only a couple of hundred years old.
Intuitively, I would suspect it originates with the Dorset, or if not acquired from them, would likely originate shortly after the Thule moved into the area, where new territories supported a ‘trial and error’ cultural phase. So we can assume a Copper culture dating roughly from 900 to 1000 in this timeline.
That gives us roughly four to five hundred years to get to Bronze.
Could the Thule get there? On digging into the matter, my thinking is that the Thule can’t avoid getting there. The preponderance of circumstances makes Bronze just about inevitable.
So, how does Bronze come about? Well, there are two routes to Bronze. There’s arsenical bronze, formed from mixing arsenical compounds. And there’s tin Bronze.
So let’s start off by talking about tin. Melting point is 450 fahrenheit, 232 celsius. Well below the melting point of copper, and well within the heat ranges of a normal campfire. It’s much easier to smelt than copper. In fact, building a fire in the right place would result in inadvertent smelting, and films of ‘slag tin’ under old campfires.
The most common form of tin, and the ore used by the ancients was Cassiterite. Cassiterite is found in placer deposits. Basically, this is a sort of natural separation process. Metals are heavier than rock. So when rock or gravel or soil gets scoured by erosional processes, glaciers, floods, river valleys, a lot of material gets washed away and moved. The heavier grains tend to fall behind, laying on top of or lightly buried, and because heavier grains or nuggets with similar density tend to be moved in similar ways, they’ll accumulate in drifts.
A post glacial landscape is a really good place to look for placer deposits, because the landscape is basically scoured and plowed up by massive piles of ice. Lighter material is moved or pushed by the weight of thousands of tons of ice on top of it, heavier and denser stuff moves less readily. The extreme cold and pressure of a glacier can crack stone to pieces, level a hill, move hundred ton boulders, or wear away at a mountain surface. And of course glaciers melt, releasing vast amounts of water, sometimes slowly, sometimes quickly, and the water saturates the environment, carrying away materials, and feeding rivers which themselves produce erosion.
All of this is by way of showing how the ice ages produced unusual quantities of mineral wealth in many areas of the north. You don’t need glaciers for placer deposits of course, though they help. Basically, any strong river system which connects to mountains has a reasonable shot.
But I’m getting ahead of the story here. So: Thule - Bronze - requires Tin (Cassiterite). I went ahead and googled, looking for Cassiterite in Nunavut, Yukon, Northwest territories, etc. For any hope of Thule Bronze (tin bronze at least, the arsenical stuff would have been the second google search).
Surprisingly, or not surprisingly, I turned up something: Izok Lake and Itchen Lake. There are recorded deposits of Cassiterite at Izok lake.
There’s also gold, copper and zinc in greater quantities. There was a gold mine at Izok lake. Gold and copper are found in accessible placer deposits, so the implication is that Tin would likely be in the same category. Basically, the same forces that make gold and copper nuggets and grains accessible along river shores and river bottoms would apply to cassiterite.
So far as I can tell, although Cassiterite is listed for Izok, it’s never been commercially mined. But that in itself tells us little. Commercial mining is an extremely expensive proposition, particularly so in the northwest territories where absence of roads and extremely harsh conditions make it difficult. You need a huge deposit to make it commercially worthwhile, and it has to be valuable, ie, the price is right. Tin’s not a high value mineral, comparatively.
So the fact that the Cassiterite deposits at Izok are not commercial in our terms doesn’t rule it out. The situation of Thule actually living in or around the area, and the comparatively smaller requirements of early Bronze age production might be completely different.
The bottom line is that there is Cassiterite at Izok and Itchen lake, and while I’m uncertain of the volume of it, or its accessibility to Thule technology (shovels and picks and musk ox plows), I think that given the little I know of the area and geology, it’s a reasonable proposition, highly probable. Pretty much a given.
Of course, the Cassiterite deposits would have to be reasonably proximate to the copper complex. If its located on the other side of Thule dominion, say on Ellesmere or Greenland or the tip of Alaska, distance would make it very unlikely that copper and cassiterite would get mixed. It might happen, but it might take a lot longer to bring this peanut butter and chocolate combo together.
Izok lake does have copper. But I took the time to look up its location in comparison to the Coppermine river. You know what? Izok lake drains into the Coppermine. Basically, its part of the drainage basin. So the Copper Inuit culture would be sitting right on top of it. Yowza!
All right, now we have deposits of Tin and Copper sitting literally right on top of each other at Izok lake, and its connected to the river which is the center of the Copper Inuit (Copper Thule) subculture. That makes bronze pretty likely.
Of course, having the two in proximity doesn’t guarantee. We need something more. We need a fire hot enough to melt or smelt cassiterite for tin. That’s actually pretty easy, considering the melting point. But you also need a fire hot enough to melt or smelt copper, tougher.
Copper isn’t that hard to melt. When I was a kid, I melted pennies. I think any kid who had a fireplace or went out camping has tried it. All you need is to get the fire hot enough.
Now, that’s a little bit tricky. In the Thule Arctic environment, energy is expensive. You can have wood fires, or fires from burning animal fat or oil. Fat or oil fires ignite at lower temperatures and therefore produce less heat. So that’s out.
Wood fires? No trees, vegetation is sparse compared to the south. There is wood in the form of driftwood or whatever gets washed down from southern rivers seasonally. But obviously, scarcity makes it more expensive.
But you can get copper melting temperatures with a little effort from wood fires.
There’s a few ways to that. One is to keep the fire going steadily, over time, it’ll build up heat. Or you can build a really big bonfire, same principle, heat accumulates. I don’t think that the Thule would go that route. Their environment is energy poor, wood is expensive, they’re not going to build big fires or keep them burning till they generate an intense heat.
The other thing is to force feed your fire. Basically, push air into it. The fire burns hotter and faster, sometimes extremely hot and fast.
Anyone who has ever had to start a fire understands that blowing or pumping air in will get your fire blazing hot. The Thule would certainly understand that principle. They live in an energy-expensive environment. They’ll certainly be masters at knowing how to get bang for their buck.
Would they want a hot rapid fire? The answer is yes. They don’t want to waste time or energy. They want copper nuggets and copper grains to be hot enough to be pounded together into a mass, and then pounded into a useful shape. The hotter copper is, the more malleable it becomes, the easier it is to work. So there’s incentive to push the temperature high and relatively rapidly. Since its basically a neolithic society, they don’t have exact temperature gauges, fire heating is more art than science, so its likely to inadvertently achieve melting or smelting temperatures on occasion.
But knowing to pump air into a fire is one thing. Knowing how to do it is another. Now, there’s a few ways to do this. The most obvious is a bellows. Did the Thule have bellows? No. No need for it.
Could they invent bellows if they needed it? Well, the Thule did have air bladders. Basically, they used sealed air-filled bags of skin for whaling or sealing, ocean hunting and fishing. In fact, there’s a picture of a sadlermiut fishing, riding a walrus-hide filled air bladder as a sort of boat. If they can make air bladders like that, all they need for bellows is a couple of valves for air in and air out. And frankly, you can control the air flow manually. So the inevitable conclusion is that if the Thule decided they needed a bellows, they’ve already got ‘off the shelf’ technology that they can adapt quickly and easily. So could they invent bellows. Inevitably.
Essentially then, we have copper, we have tin, and we have within Thule culture, the existing skills and technology that can be readily adapted for making fires hot enough to melt copper, and motivation for reaching high temperatures to facilitate copperworking.... Well if you have that, then Bronze is inevitable. The only question is when.
Potentially, given the confluence of factors, it could have happened any time shortly after copper-working and occupation of the Izok lake area. So potentially, as early as 1000 CE.
Potentially, yes. Likely, not. Of course, population densities are low (higher than OTL, but we’re still talking hunter-gatherers here) and distribution networks are small, and there’s not necessarily a lot of demand for copper, and not a lot of labour producing it.
Get to the agricultural era, population expands exponentially, and trading and exchange networks expand dramatically. Both of these things produce much higher demand. And as I’ve pointed out, the labor pool producing copper expands as well. So it would not be unrealistic to start the Bronze era around 1200 to 1250, at the dawn of the agricultural period. That wouldn’t be unreasonable at all. Any time after that seems reasonable to me.
Now, I’ve chosen not to jump the gun and place Bronze between 1200 and 1300. Rather, I’ve delayed it until 1400-1450, or basically two hundred years after it becomes feasible and realistic.
You know what I call that? I call that ‘not wanking!’ I call it conservative.
I mean, okay, we’ve started with basically a culture of stone age hunter gatherers and in about 500 years I’ve moved them up to the start of a Bronze age technology. I admit, that’s hyperspeed. But it’s also reasonable, highly reasonable, and cautious under the circumstances.
So why 1400-1450? A few reasons. First, the Thule expansion south brings them into the treeline, which makes firewood much more available, either on the site, or simply floated down the river to where its needed. More wood available to the Thule makes energy cheaper, and that alone might fuel experimentation.
Also, in 1400-1450, the population is pretty substantial, much more so than 1200-1250, so more labour, more demand. More elaborate trade networks.
Thule population is going into flux. The medieval glacial era is causing a lot more people to be on the move, so there’s social instability, it’s a more chaotic time. That produces more experimentation. Existing technologies, existing ways of doing things, get second looks in situations like that. There’s more willingness to experiment, to do trial and error, or to work from theories or analogies. There’s more willingness to take ‘off the shelf’ technology and apply it in new ways. Or to use the idea of existing technology, such as pycrete mixtures, and wonder if the principal could be applied elsewhere.
And by this time, there’s much more elaborate trade routes and more goods travelling through these routes for longer distances. Which means that the Copper country may encounter Iron, either the meteoric Iron from Cape York, or even bog Iron from Norse contact.
The point of the ‘slice of life’ excerpt is that encountering a metal with remarkable properties, the Copper Thule can only consider it a form of copper, and speculate that this is copper which has somehow been modified. So they set on the road of trying to turn copper into iron - which doesn’t work, but gets them bronze.
Anyway, I think I’ve beaten this to death, my point is made. I've got bronze because I don't have the option not to have bronze.