Quote Originally Posted by r0bsk1 View Post
Plastic is a resin in its liquid state.
Actually it's the other way round - some resins are called plastics in their solid state. Plastics belong to the set of materials called resins, hence I specified plastics to narrow down the discussion since I suspect these moulds are for thermoplastics, so stating plastics is equally, if not more, accurate. The reason for this supposition is the user's previous posts regarding an injection moulding machine.

Anyway, what material are the moulds going to be made from? If aluminium then this article suggests they should be plated with nickel.