Cold iron armor sickens certain creatures that touch it. A creature with weakness to cold iron (such as most demons and fey) that critically fails an unarmed attack against a creature in cold iron armor becomes sickened 1. A creature with weakness to cold iron is sickened 1 as long as it wears cold iron armor.
Low-grade items can be used in the creation of magic items of up to 8th level, and they can hold runes of up to 8th level.