Resource gathering is an important part of every crafting system. An important resource would be ores and minerals mined from the depth of the earth.
It would, of course, be unthinkable for a wizard to take a pickaxe and perform manual labor to excavate minerals. Like everything in Pecosia, there is a branch of magic dedicated to these kinds of jobs: Geomancery.
Geomancery is the art of using magic to sense minerals in the earth and getting them to the surface. A geomancer hunting for ores needs two spells: A detection spell which tells him where the minerals are hiding and a mining-spell which gets them to the surface. More advanced minerals do of course require more advanced geomancery spells to find and mine.