My totally unreserved guess is that there are not very many on a per capita basis, but there are probably about 10-50 working smith's per state. They do architectural work, historical pieces, education, sculpture, and all sorts of other stuff, if you include farriers (who deal with shoeing horses, but it's really a more technical trade that deals with horses gaits and health).
So give they are using more or less the same methods of a blacksmith of yore and the etymology works, they would seem to be a blacksmith to me.
Black ~> iron smith, Green ~> copper smith, White ~> silver smith
Ref: https://blog.lostartpress.com/2015/07/30/forged-forged-nails...
https://www.bradfords.co.uk/ironmongery-fixings-adhesives/na...
https://www.heritage-store.co.uk/traditional-nails/2043-cut-...
very likely the hand-made ones are for restoration projects where you need to be as faithful to the original as possible.
or, more commonly in timber framing, rectangular profile.
Hammered in thin dimension between the grain, long dimension with the grain, maximising wood|metal surface area, minimising splitting|cracking forces.