Thanks for your info 2152hq. Learning the process sounds a bit like learning rust bluing, about anyone can turn the parts blue, but consistancy and quality are relative to years of experience.

BTW, I saw your engraved Hepburn on another post, extremely well conceived and executed! and great lettering, an under-appreciated skill!

Another pic of the Marlin showing rust blued barrel and Mag tube, charcoal blued forend cap (Turnbull) and nitre blue mag cap and screws.(Mike Dubber engraving)