When I was a young thing, relatively ignorant about various sorts of kitchen chemistry, I inadvertently invented am indestructible polymer.

The pot's long gone, but I'm curious about what, if anything, might have solved the problem.

I'd gotten several pieces of cheap unseasoned cast iron cookware, and successfully seasoned the shallow frypans. There was a dutch oven type pot, however, and here my problem began. The pot being quite deep, it needed quite a bit of (likely canola) cooking oil to coat the interior. I stuck it in the oven on low heat, as I'd done the others, and unfortunately forgot about it for several hours. The oil, once hot, seems to have run down the sides of the pot, leaving a bit more than a quarter inch of oil in the bottom. This oil had gelled into a kind of hard transparent yellowish rubber. It could be dented but not removed with a sharp instrument. It was tougher than anything I've ever seen in a cookpot, for sure.

I soaked the pot. I boiled water in it. I boiled detergent and water in it. I boiled vinegar in it. I can't remember everything I tried, but I had no success at all in even reducing the glossy surfce of the stuff. The pot was a write off.