Cast iron is manufactured in a very furnace stoked with alternate layers of coking iron then poured into molds. Following the iron cools off, the sand is cleaned off. The Chinese were the main to work with Forged iron[1] through the sixth century AD using it as assist for pagodas https://www.finduslocal.com/local-business/california/los-angeles/naddours-custom-metalworks_1525-e-edinger-ave-santa-ana-ca-92705/