You can buy graphite rods, if you get one that is 4-6" diameter you can turn it on a metal lathe and make a crucible, turn a lid to match. Should do fairly well in a furnace, forge, or giant rocket stove!
You can take the rods to a machine shop too, it makes a terrible mess!
Look up iron bloomery furnace , they are a clay one time furnace used to make primitave iron from ore, actually now that I think of it they are a rocket stove of sorts!
You get a bloom of iron that once wrought out on the anvil makes.....wrought iron! But steel is just iron with carbon levels that exceed what is considered iron.