The shipyard steel disc that we tried to bake on….and we did give a fair old shot at it, had almost an 'engine turned' surface on it. We seasoned it, we baked on it, we roasted it and seasoned it some more. We scrubbed it and started again, and again, and still every damned thing stuck in a neat pattern where the heat came up from underneath. Didn't matter whether we used gas (her) or electric (mine) cookers. It just wasn't worth any more trying.
My cast iron girdle (and my MIL's old aluminium one that Son1 pounced upon and carried off when I said I couldn't use it on this hob) both started rough, that orange peel finish that mrcharly mentioned, but both are now flat and shiny. Both bake superbly well, as does my pizza stone that is now so dark that it would pass for iron to look at and not ceramic.
I use mine daily at times. It
was every single day in life when my sons were younger and feeding them was like filling bottomless pits
They are, I think, nowadays vastly under-rated kit. I take one with me when camping too. Fresh bread, pizza, scones, oatcakes, pancakes, tatties scones, bannocks, tortillas, nan, bere cake…..every kind of baking under the Sun, and most traditional flat breads too.
Interesting to hear of the metal bakestone though; my ceramic one's now twenty years old, and I haven't dropped it yet, but I suppose I only need to do so once….
cheers,
Toddy