It took the British iron industry a hundred years to transform from a small producer at high cost in the early eighteenth century, to become the leading supplier of iron products for the world market by switching from charcoal fuel to coal fuel techniques. In a long-drawn transition, the coal-using techniques were transferred to Belgium, France and Germany, in part indirectly with British iron exports embodying the new technology. Behind protective walls in Belgium and France, new ironworks imitated the British model. Traditional ironworks succeeded in integrating only parts of the new technology (i.e. puddling) and increased their productivity by applying modern fuel-saving strategies. Thus old and new coexisted for a long time. The demand for low quality railway iron made most of the British-type ironworks on the continent profitable. From 1860 on, coal iron was produced in ever better qualities which left only niches for the high quality charcoal iron.