A lodestone is like a battery, made from numenic ore that has been refined so that its innate magical properties become exploitable via an aura of charged, magical energy. Refinement of numenic ore requires significant metallurgic skill because numenic ore is radioactive and highly unstable.
Lodestones are encased in metallic spheres and naturally float above the ground due to their magically charged auras. The size of a lodestone is directly proportional to the amount of energy it contains, and its color is related to the type of numenic ore from which it has been refined.
Lodestones can be used as power sources for Clockwerk technology. An unsheathed lodestone is extremely dangerous and can vaporize matter on contact. As a lodestone's magical energy dissipates, the sphere darkens, until it loses its aura entirely and becomes cold iron, falling to the earth.
Some of the most talented metallurgists and alchemists serve the Kingdom of Vanis in The Fulcrum, the largest-scale production facility of numenic ore in the world.