Yllurian

The most valuable metal in the world is not iron, as one might think. Though iron can be crafted into steel, and subsequently used to craft arms and armor, to reinforce large structures, or to create clockwork machines, it is nowhere near as valuable as yllurian, the most important magic-holding material yet known to mortal-kind.   The mages among my readers will know well that magical energy can be stored in different amounts and in different concentrations (as a Druid of the Root, I was fortunate enough to wield a vaunted living-wood staff with an yllurian vein inlaid into it, allowing it to hold all but the most powerful spells a druid of my class could cast). Yllurian has the most storage capacity per area of all the precious metals, and it can be alloyed into steel. This allows weapons made with it to be virtually unchanged in physical performance while also being able to hold magical power, often manifested in some sort of elemental effect or an impact shield, if alloyed into armor. Of course, a more advanced arcanist can imbue more sophisticated magicks into the yllurian, but the most typical effects would be something like a flaming sword or sword of radiance.   Pure yllurian blades do not retain their edge quite as well as infused blades, as yllurian is a softer metal -- more akin to bronze. Of course, this limitation also applies to shields and armor -- anything made of pure yllurian will have more give and be easier to cut with steel than its normal steel counterpart. Therefore, yllurian is most often alloyed with steel for practical battlefield use, allowing the hardness and effectiveness of steel to combine with the magical potency of yllurian (steel is quite a poor conductor of magical energy). Besides, a breastplate of pure yllurian would be prohibitively expensive, and would only be affordable to the wealthiest of nobles.   Battlefields are not the only place for yllurian, of course. Many field-laboratories and travelling mages need access to a store of energy in order to prepare and channel spells easily without fatiguing themselves. To remedy this problem, relatively small chunks of yllurian are shaped and sold to fill this need. The chunks most often come as spheres or cubes, but can be shaped to fit into specific cases if necessary. A sphere with approximately the diameter of a normal dragon egg (one foot across, for those who are unaware) can hold more than enough energy for most field adventures, and is the most a human or elf can reasonably carry besides. For larger applications, such as in massive, spatially-fixed laboratories, cork is often used, since it is much cheaper and can be bought in higher quantity.  

Sources

The largest sources of yllurian are Abbasynia, the Thousand Isles, Vashyl, and Nörn, in that order. Somewhat counter-intuitively, Vashyl and Nörn profit the most from their yllurian sales, even though they have the least raw amount. The reason being the mass organization that goes into mining in those regions. Since Nörn is controlled, mostly, by a single human kingdom (the smaller dwarven kingdoms also compete with the Nurnen, but they don't make much of an impact on overall sales), and Vashyl is controlled by dwarven and goblin cabals, pricing can be easily fixed. These organizations are also on good terms with the major importers of yllurian, the elven kingdom of Jin-El Aethis, and the Southern Draconic Empire.   Thousand Isles imports are somewhat complicated by the fact that there are so many small kingdoms, each with competing claims on the yllurian deposits. Their constant infighting has caused many of the most productive yllurian mines to change hands several times over the last few years. This, in turn, has brought the regional price of the yllurian down in an effort to attract buyers. The short distance from those mines to Jin-El Aethis is also a strong incentive for the elves to invest their coin, but the inherent instability and piracy that plague the reason seem to be just as strong an incentive to stay away -- for who wants to fund a mine that might be out of their control the very next year, or make a purchase order with a kingdom that may cease to exist? Instability has crippled the mining industry in the region as a result of investor hesitation to put forth a significant amount of coin, but the recent entrance of the elven navy into the region is sure to greatly affect the viability of mining operations in the region. There are some who even speculate that the elven interference in the region has the primary goal of establishing elven-run yllurian mining operations that would end dependence on foreign yllurian imports...   Abbasynia is somewhat different from the case of the Thousand Isles. The exports from the region are extremely cheap, and they most often arrive in their destination ports untouched by pirates. However, there is simply not much yllurian flowing out of the region, due to a multitude of factors which I shall now divest to you, dear readers. The first, and perhaps primary, reason for the poor export industry of the Northern Human Realms is the simple fact that no one wants to buy from them -- not even their neighbors to the south. In fact, the Southern Draconic Empire has an active embargo on the product altogether, if it comes from the north. The dragons view their northern neighbors as a threat, mostly kept at bay by the murderous jungle between them, and the mountains in the west. Keeping their unpredictable neighbors in check is one of the primary goals of the dragons, and so they refuse to help the economy of Abbasynia, preferring weak northern neighbors that are only strong enough to war against each other. The elves, on the other hand, have moral qualms with purchasing yllurian from such a source -- they detest the perceived barbarism of Abbasynia, and prefer to trade more unconventional items (trash, really) for yllurian of equal value. For example, much pirate weaponry is seized by the elves, who have no use for them, yet weaponry is in high demand in Abbasynia and will result in a high return in yllurian for the elves at only the cost of some rustic weaponry that is useless to them anyhow.