I know I have seen a casehardened picture of an iron framed before myself. Somewhere online or in a book and it was obvious that it was casehardened.
I am with Driftwood. Mine is too nice to mess with. I should really duplicate his picture as I have duplicated his rifle also in 44/40. It has been absolutely a blast to own and shoot. My only regret is the rear sight is not to my liking but I have not figured a solution yet. Looking but not doing for now.