Opinion is split over wrought iron vs mild steel from a blacksmith's perspective, especially if they have access to a powerhammer. It was sold in many different grades and the cruder/coarser/cheaper grades (muckbar) can be very pretty when etched. As Launditch points out old farmland is a good place to go hunting.
Knifemakers are sometimes very interested in WI, it can be etched to look a bit like pattern-welded steel. The cruder the iron the better the effect.