Hi Trev,
I have an 1957 Ariel NH350 (in bits!) that has the hubs but they're just a rough cast finish as Markus described. I've had the bike years and it is totally unrestored.... I also have a rear hub bought in error (it's a BSA one - subtly different!) at a jumble some time ago, same finish..
Polishing seems to be a more recent phenomenon !!
HTH ,
Cheers,
Adrian