Abraham Darby and Coke-Smelted Iron

Iron had traditionally been smelted with charcoal, made from wood, which limited output as forests were cut and charcoal became expensive. In 1709 Abraham Darby I, a Quaker ironmaster at Coalbrookdale in Shropshire, successfully smelted iron using coke, a purified form of coal. Coke could support larger furnaces and was far more abundant than charcoal. Darby used his iron for cast cooking pots at first, and his family business expanded over generations.

Coke smelting spread slowly, because early coke iron was suited mainly to casting, not to the wrought iron that blacksmiths needed. By the late 18th century, however, coke furnaces dominated, and iron output rose sharply. The Darby family's Quaker networks of trust and credit also helped the business grow. Coke smelting linked the iron industry to coal, tying Britain's two great industries together.