per Don Stith
'The few Hawkens in good enough condition to see original barrel finish are blued. I like the color I get by slow rust brown, followed by boiling the barrel in water.
The proper finish for the other iron parts,trigger guard,buttplate , lock,etc is case hardened. Not the highly colored case of modern firearms but a mottled grey case that some of the early makers called forge casing.
The barrel, rib and thimbles were blue. The breech and tang were cased as well as the lock, butt plate, trigger guard, trigger bar, entry thimble and nose cap. Not the highly colored case of modern firearms but a mottled grey case that some of the early makers called forge casing.
The blue is fairly dark and may be slow rust blue rather than charcoal (NOTE: makes sense since rust blue would have been the more common method for the period during which the Hawken shop was in business). If doing the rust blue, don't overpolish or you get too bright a color. It is not the deep translucent blue seen on European guns. I usually just do a satin brown followed by boiling in water to duplicate the color