I recently picked up a relatively cheap #3 Iron Mountain with larger than normal striations around the part of the pan that gets ground down after being broken out of the mold. It looks to me like the grinding was done at the foundry, given the evenness of the striations and appearance that it was done in a single pass. Was it done at the foundry? Does this show up on a lot of iron? How severely does this sort of imperfection impact collectibility and/or resale value? That ruler is showing inches.