Ill have to say if you want to consider Master Blacksmiths you need to include Frank Koralewsky of Boston 1872 - 1941
His wrought iron carving and repousse is beyond compare !
even Samuel Yellin looked up to him .Samuel and Franks work was shown together as a metalworkers exhibit in Detroit in 1911 for the Detroit society of arts and crafts his Work Can be seen at Harvard , Yale, Boston College
as well as many religous buildings around the USA He forged most of the iron at the Cathedral Church of Saint John the Divine in New York city.
Samuel yellin and Frank work on many of the same buildings together
because many of the top architects of his day considered Sam and Frank the best .if you want to see some of his work go to flicker and type in Frank Koralewsky Snow White Lock or go to hammersmithstudio.com look under history
incidently im in the process of writing a book on him , but it is taking me forever to do the research, Cheers Carl Close jr Concord Ma