In 1961, when the ironmaking site in the late Southern Song Dynasty (around 127) was excavated in Xinhui, Guangdong, China, coke was found in addition to slag, limestone and iron ore. This is the earliest example of coke used in iron smelting in the world.
in Britain, in 179, Abraham Darby I used coke instead of charcoal to make iron, which was successful and obtained a patent for this technology.