Compare and contrast the uses of the iron triad and the use of the coinage metals

he iron triad has the most variable oxidation states from + 6, etc. The coinage metals have oxidation states of + 1 except for copper which can also be + 2. The zinc group have common oxidation states of + 2 except for mercury which can also have + 1. The coinage and zinc groups cannot have oxidation states greater than 2 under normal conditions.