What should we be doing about these conflict minerals from the Congo, eh? Even MPs are raising Questions in the House on the topic.

It's certainly true that some of the violence in Eastern Congo has been associated with access to minerals. What's a lot less certain is which way around the causality goes: is it people being violent to control the minerals trade or is the minerals trade a way to finance violence already inherent?

There are those who know the situation on the ground a lot better than you or I do who argue that it is the latter. There are campaigners who insist that it is the former as well. Perhaps most importantly, why would anyone on a tech site be interested?

That last is the easiest to answer. The mineral that really has everyone hopping is “coltan”, the correct name for which is columbo tantalite, and which is the source of all that lovely tantalum which makes the capacitors which are such a vital part of just about every tech product.

It is possible to make them from niobium, although they'll be larger and less efficient, but unfortunately the columbo part (for niobium used to be called columbite by the Americans) is a major source of that metal. We could go back to aluminium, but then we're back to the world of brick-like phones.

So, it is a matter of some importance if rape, murder and torture are being used to supply us with part of the industry's lifeblood. It's akin to the recent arguments over “blood diamonds” although no one is saying it's exactly the same. The blood diamond wars (in Angola, Sierra Leone etc) seemed to be more about having a war to get control of the mines so as to be able to finance a war to get control of the mines. Eastern Congo has other conflicts. It wouldn't be at peace even if there were no minerals at all.

The general solution being offered is that somehow we should make sure that minerals mined under violent conditions, or mined to finance violence, should not be allowed to enter the supply chain. Dependent on the mineral this will be more or less effective. However - and I do hope I'm not thought too cynical - this seems to have morphed into something of a boondoggle.

As background, the four metals under discussions are known as the “3Ts plus gold”. Tantalum (from our coltan), tin (from cassiterite), tungsten (wolframite) and gold. To a certain level of accuracy (not a very high one, true), columbite, tantalite, cassiterite and wolframite are actually the same mineral. They've all got a bit of Nb, Ta, Sn, W in them, and we apply the different appellation dependent upon which is the major content. And yes, tin slags from cassiterite processing end up at a Ta plant and Ta plants always have tin extraction circuits.

There are serious problems with stopping tin or gold entering the supply chain: tin extraction, by definition, is a Bronze Age technology as spoil heaps all over Cornwall show us and gold older than that. If you've a forest (for charcoal), labour and can build a bloom furnace then you can extract both of them from the ores found in DR Congo. It's easy enough to then sell these, completely unidentifiable by now, roughly processed metals into the scrap supply chain.

So efforts concentrate on the coltan, for extraction of the interesting metals from that is not easy at all (wolframite is a very minor player indeed in all of this). And there's a certain political piquancy to being able to point to a mobile phone and screaming that “people died for that!”.

Getting to the choke points