Iron is used in three commercial varieties.
1. Cast iron or pig iron:
It is the most impure form of iron and contains two-five percent impurity mainly carbon. This from is hard and brittle. It is used in making gutter pipes, furniture gutter cover (manhole)
2. Wroght iron:
It is the purest form of iron and contains 0.12-0.25% impurity. It is soft and malleable. It is used in black smith. It is used in making agricultural tools, chains, anchor, etc.
It is intermediate form of iron and contains 0.5-1.2% impurity mainly carbon. It is mostly used as construction materials, etc.