 It wasn't until 1840 when David Thomas introduced Welsh hot blast technology to the Lehigh Crane Iron Company that anthracite was successfully used to smelt iron.It was indicated that using anthracite saved up to 25% in the production of iron, and that the quality of the iron was also superior (Adams, “US Coal Industry”).By the 1850s anthracite was used in the manufacture of about half of all crude iron produced in the US.