Identifying Cast Iron Skillet - with weird pattern My mother gave me an old skillet she had, and to me, it looked like a normal cast iron. I wanted to 'clean' it the way I normally clean and season my other pans, by scrubbing it with chain mail scrubber, then heating it up and oiling it. On the back of the skillet it just says "KOREA 8" SKILLET"

However when I got to scrubbing more layers came off than I anticipated and now it has me wondering if it is cast iron or something else? It has a weird pattern that was exposed that I have not seen before on other cast irons. The lighter rings in the spiral rust when exposed to water and let to air dry.

Anyone able to identify? Can I proceed with seasoning it in the oven with oil as regular?
I am not an expert on cast iron, but I believe this just means that it's a machine-milled piece, instead of one cast from a mold. There's nothing better or worse about it as far as I know as far as performance goes, I think it just means that it's a relatively newer piece, since pans made from casting tend to be older. Some people prefer the older ones.