Orichalcum is a gold-colored magical material. It is extremely hard when fired properly, and was commonly used for magical armor and weapons during the Mage Wars. However, while it is a potent magical amplifier, it is not effective as armor. Unlike steel (also common at the time), orichalcum does not bend easily, thus making it poor at absorbing impact. It can withstand tremendous impact, but tends to transmit most of the energy directly into the wearer.
Orichalcum is by far the most common of the high-level magical materials. It is more rare than gold and difficult to work with, requiring extremely high heat (hotter than achieved by conventional means); thus the material has not found many uses in the industrialized world. Ornamental jewelry is the most common non-magical use, as it is harder than gold and thus less prone to damage. However, the production costs make orichalcum jewelry extremely expensive.
It is still highly sought-after by mages, and the easiest to obtain. Orichalcum-clad towers were not unheard of in the Mage Wars. There is no estimate on how much Orichalcum has been mined, but new deposits of the ore are occasionally found and while expensive it is not difficult to obtain.
Three grades of Orichalcum exist: "gold", "orange", and "red". Gold Orichalcum is far and away the most common, and it dark orange and gold in color, streaked with veins of red. From this, a complex refining process can seperate out the red materials, creating red and orange Orichalcs. Pure red is very rare and powerful as an amplifier, and was long thought to be the 'source' of power in Orichalcum. The orange leftover material was sometimes discarded, but being similar enough to gold was often re-constituted into metal. Orange Orichalcum is still extremely hard and tough, and makes slightly better armor than Gold Orichalcum. It also still has potent magical properties, though they are considered slightly harder to 'tap into'.
Because Orange Orichalcum comes out of the refining process as a powder, it is also frequently used in electroplating.
Stories of a dark green orichalcum have long persisted, but were believed to be rumors until the first appearance of Samuel Fate, who wore armor made from it. He also gifted a gauntlet of the material to Hunter Jusenkyou. While green orichalcum was still exceedingly rare (Fate chose it for its extreme scarcity, not its power), Mithril was completely unknown to his empire, indicating that in the region of the known worlds, mithril is actually comparatively common.