Most players in this little spaceship game are familiar with Technetium and its outlandish price, and veterans will recall Promethium and Dysprosium before it. What people are less familiar with are the interactions that drove those prices to their astronomical highs. Importantly, these same interactions drive the market prices of all raw materials in Eve.
Baskets & Bottlenecks
Understanding how raw materials are priced in Eve requires combining two concepts: Market baskets and bottlenecks.
A basket refers to a group of goods that a consumer purchases together. In retail, stores often discover these things through research and analysis. A common and likely apocryphal example is of a grocer who realized that customers that bought diapers often bought beer as well, and so saw a boom in sales for both after placing them together. In Eve terms, a pilot who purchases a Vagabond can be counted on to purchase a set of fittings... and probably an Exotic Dancer as well. Alternatively, for an example more relevant to the topic, a pilot purchasing Tritanium for his own use will very likely buy Pyerite, Mexallon, and other minerals.
A bottleneck occurs when a system is limited by a single component. In our terms, it is the item or items within a basket which is least well supplied relative to overall basket demand. If I have 10,000 Tritanium and 6,000 Pyerite and the item I wish to build requires 1,000 Tritanium and 500 Pyerite, than no matter how hard I try, I can't build the twelve units that I have Pyerite for - Tritanium is my bottleneck. Of course, in this situation I simply buy more Tritanium, and all is good. Project this phenomenon game-wide, and you have the bottlenecks in Eve.
The astute reader has probably assumed that I'm actually talking about moon minerals. They're half right - moon minerals are the most common example of the bottleneck & basket interaction, but we'll certainly revisit regular minerals later. Moons have a fixed output, and of course there are only so many of them. It goes without saying that if you're trying to create a resource system without bottlenecks, "fixed output" and "fixed number of sources" should scare the hell out of you. Even with careful balancing, it's all too easy to create a situation in which the supply of one resource comes up short.
In the "old days", prior to Dominion, the end state of this system was that Dysprosium and Promethium were the bottleneck. As a result, they were immensely valuable, reaching over 180,000 isk/unit, or 13 billion isk per month per moon before fuel costs. After alchemy - a means of producing intermediate materials with alternatives to the Dysprosium or Promethium - failed to have any effect, CCP took action again, tweaking the blueprints for Tech II components in an effort to spread some value to less valuable moon materials. Instead, as they were warned, Technetium became the new bottleneck. That Technetium is restricted to the northern regions of Eve only exacerbated the problem.
Now, once again, CCP has tried the alchemy solution. While the new alchemy did a much better job of lowering Technetium prices, it did nothing to spread value through the basket - only platinum, cobalt (both alchemy ingredients) and Neodymium (the next in the bottleneck line) rose in value.
CCP has promised "Soon™" to revisit moon minerals, with the stated intent of "changing how they are produced." Many players take this to mean Ring Mining. Only time will tell, but we can only hope that CCP has learned its lesson.
Unfortunately, recent history suggests otherwise.
The Drone Alloy Fiasco
The drone regions were introduced to the game in Revelations I, the winter expansion of 2006, and featured Rogue Drones as their NPC dwellers. As most players are aware, these rats are unlike others in the game in that they have no bounties - a player must loot the alloys from their wrecks and refine the minerals contained within to receive their payout. While this system was originally met with plenty of complaints from players ("I have to do extra work to get paid!") pilots quickly realized that their extra work was met with extra reward, as well. Over the years, population within the drone regions grew, and across the board, mineral prices dropped.
The drone regions had effectively eliminated bottlenecks in mineral production. Everything was supplied in enormous quantites, and everything was cheap. To highsec miners, this was of little consequence - highsec minerals were already cheap; if you're mining 23/7 the difference between 10 million and 15 million an hour is academic. In nullsec it was a different story. "Gunmining" had a particularly large effect on the price of high end minerals, dropping their price over time by upwards of 80%. Supercaps became a common thing, enormous wars became the norm, and so demand followed supply, inflating in a big way.
In an effort to change this, CCP took the combined action of removing Meta 0 (manufacturable) loot from NPC drop tables, and nerfing Rogue Drones by giving them bounties in place of the alloys they once dropped. The expectation was that the high end minerals would spike in price again, and the casual and hardcore nullsec miners alike would reap a great bounty, which they did.
At least, until reality caught up and burst the bubble.
A couple of things went awry with CCP's grand plan. Mining had changed significantly since the drone regions were introduced. Mining yield had increased dramatically thanks to Rorquals and Tech II mining links, while theoretical supply was virtually infinite due to gravimetric sites that respawn almost instantly after being mined out. When prices for high-end minerals spiked, miners reactivated long dormant accounts and rushed to the belts, and they were able to make up the shortfall left by the nerfs. Meanwhile, upwards of 70% of low ends were also supplied through gunmining and loot drops, a fact which CCP may not have considered. While prices were suppressed for a time by enormous stockpiles, those eventually broke, and the ramifications are clear on the market today - the mineral bottleneck flipped, handing highsec miners a bonanza, while nullsec is worse off than ever.
Unlike moon minerals, the sources are not fixed. Veldspar and other low end minerals are plentiful and abundant in empire, and virtually untouched in Nullsec. Unfortunately, there almost certainly are not enough miners to make up the difference in Empire, even with it turning into an laughably safe carebear themepark, and the nullsec low-end supplies are untouched for logistical reasons. On the other hand, nullsec miners have demonstrated the ability to fully supply high ends, even meeting the outsized demand left by drone region supply. As a result, nothing is likely to change without drastic action from CCP.
A note on numbers
"How can you make these conclusions? Where does 40%/70% come from?" By mining data from various devblogs and interviews and making some judicious assumptions, painting an approximate picture of Eve-wide mineral production at several points early this year was possible. While the estimates are not exact, the conclusions clearly are spot-on.