Steel/Wrought Iron ?

[truck]

I've been finishing the destruction on a couple of 150+ year old barns. I certainly haven't made any finds of archaeological significance, but every once in awhile I do get something. I've been finding a few eyes that were obviously made on a forge and if they might be iron, I was going to keep them for future knife parts. What one question is, when did steel replace wrought iron in common usage? The other question concerns bones. I just found a couple of jawbones. How do I retain the teeth as the jaw dries? These would be for small neck knives and wouldn't look like much without the choppers. Thanx!