An iron pot is a porous material that tends to rust. As a result, the pot must be dried before use. Drying creates a thin layer of oil and carbon to protect the surface from sticking to the pan.
Many metals have good thermal conductivity, but the chemical is too unstable to be used for food processing. But in some cases, the pot can be made of very unstable metal material, and then coated with a layer of other stable material.
The range of metal material used for making pots is very narrow, because the pot needs good thermal conductivity and chemical stability, otherwise it will change the taste of the food.
