Burmite is a unique substance, found only in Carteth, which absorbs and retains magical energy. Though having many of the qualities of more typical metals, Burmite is most commonly found in near-crystalline structures deep underground.
Once mined, burmite is processed in many ways and sold to mages and companies, who seek it for its usefulness as a magical power source and accelerant. It can be most readily bought by mages as either a powder or as solid bars, both of which are usually pre-measured into common quantities needed by casters. As a result of its usefulness to them, however, as well as the expensive nature of extracting it, it currently trades for about 8 gold pieces a pound.
In 1205, Altore Speirt developed a technique for impacting burmite into various metals, along with his partners, Arnold Purcell Frie and Linus Delinius. This created new and powerful industrial applications for the substance, and ushered in a golden age of Feiltan innovation.