Bolts can be either ferrous or non-ferrous, meaning that they either contain iron (ferrous) or don't contain iron (non-ferrous). So what's the difference between the two, and what are the characteristics of each? Obviously, the biggest difference is that ferrous bolts contain iron, while non-ferrous bolts do not.
Ferrous metals are defined as those metals that contain iron. Non-ferrous metals do not. One of the major distinctions in specialization is whether foundries work with ferrous metals, non-ferrous metals, or both. The definition of a ferrous metal is any metal that contains iron; non-ferrous metals do not.