English ironmaster usually credited with having been the first to smelt iron ore with coke, which is a hard, foamlike mass of almost pure carbon made from bituminous coal.

Charcoal, made from wood, had been exclusively used for smelting iron until Dudley began experimenting with coke, or, as he called it, “pit-coal.” Such experimentation had been encouraged by the English government, which was concerned about the rapid destruction of forests for fuel. Dudley obtained a patent for his innovation in 1621 and was soon producing a record seven tons of pig iron per week at the Hasco Bridge ironworks owned by his father, Edward Sutton, 5th Baron Dudley.