I was talking about my skillet this weekend and my grandfather told me he had 3 CI skillets from his mother. She died in 1940 so not sure how old they are. They had a bunch of build up on them on the bottom and outside. So much that I thought it was damage to the cast iron. I have been cleaning on them for a couple days. I have one small one seasoned and two more to go. It is amazing how slick the surface of this vintage stuff is compared to the newer stuff. Can't wait to get it all cleaned up and start using it.