After Conflict Minerals Comes The Death Metal: Tin. And It’s Apple’s Fault Again.- by Tim Worstall (Forbes Magazine – November 24, 2012)

Given that the well meaning types have now solved the problem of conflict minerals through the Dodd Frank act and the requirements for companies to report their use there’s obviously a new frontier needed for the well meaning to conquer. And of course the conflict minerals problem has been solved as M-23′s move into Goma shows. Now that people can’t make money out of mining in the area no one at all is fighting for control over the area are they?

The Guardian tells us all about this new frontier being staked out. It’s tin mining in Indonesia now. Much of what they actually say they get right. There is indeed a belt of alluvial tin ore ranging from Burma down to Indonesia. In the poorer countries there it is indeed mined by very primitive methods. Miners are badly paid while they do so and yes, some of them die while they do it. The poor pay and primitive methods are because the places are poor: they’re actually the exact same statement.

Just as a little background, and without too much technical guff. The only ore of tin that we care about is cassiterite. Sometimes we find vast mountains of it as in Peru. Sometimes small mountains of it as in the Erzgebirge/Krusny Hory on the German Czech border (disclosure, I’m currently waiting, rather nervously, to find out whether my application for a mining license there is going to be granted. I’m not looking for tin but for the closely related, in an ore sense, tungsten but tin will be a by-product and it’s the main product of the mine right next door.).

And sometimes we find that vast mountains of it have been worn down by erosion and that the cassiterite is now spread through the silt and sand of an ancient estuary.

This is what the SE Asian tin sources are and why they are described as “alluvial” deposits. The cassiterite makes up some fraction of the standard sand and river silt there.

Back an ice age or more sea levels were much lower than they are now and that silt has been deposited right across the area, sometimes above current coastlines, sometimes below them, close inshore and well offshore too.

The extraction method is really quite simple. Dig up, suck up, that sand and silt then separate the heavier cassiterite from the lighter sand and silt. While they use a slightly different method it’s exactly the same principle as those cascades of wooden troughs you see in every Western movie about gold mines. The cassiterite sinks faster so the first stuff that sinks is the cassiterite.

Getting the tin out of the cassiterite is pretty easy: a hand built furnace and some charcoal can be used to do it although obviously modern machinery can make it more efficient. That ease of extraction is what made tin one of the very first metals that humans really learned to use. It is, quite literally, Bronze Age technology as bronze is copper and tin.

Some of the earliest deposits exploited were those in Cornwall and Devon, in the SW of England. Some of the little mountain streams would have eroded and then collected deposits of that cassiterite: alluvial deposits again. The higher areas of both counties are littered with the remains of several thousand years of their exploitation. We’ve good evidence of Cornish tin ingots in the Eastern Mediterranean by about 1,200 BC, taken there by Phoenecian traders.

For the rest of this article, please go to the Forbes Magazine website: