Smelting Iron Technische Fakultät
The first reaction takes place between silicates always containing SiO 2 and iron oxide (= iron ore). It produces an ironsilicate, Fe 2 SiO 4, called fayalite, a major component of pretty much all antique slags. SiO 2 is pure quartz or "silica", rather common by itself, but most silicates and thus most "rocks" will also do.