Antimony is occult knowledge dealing with demonology, creatures of the dark and necromancy.
Rooting out antimony is one of the primary tasks of the inquisition, and certain groups tend to fall under suspicion more than others. Reeve Mammonists, Li-Hilan Manja practitioners, Eskatonics seeking wisdom from forgotten entities, all are familiar archetypes to the citizens of the Known Worlds. Be they guild, noble, or churchmen, all are suspect.
Much of Antimony inspiration comes from a a text in the Omega Gospel, specifically the Chronicle III, 6:12-18 which makes reference to
The infamous guide to this is the Draco Codex.