What Happens When You Make Steel?

There were, at a certain point in pennsylvania, something like, well, more than a hundred steel mills. Even the j c penny, even stay at home moms had to make a steel in their bathtub. There's all that stuff in the rock that's not iron, and you have to kind of cook it off. And then when you take iron and you turn it into steel, there's more stuff in iron that you don't want in steel.