Glad to see the extra pics here. I was to chime in on IG, hoping to see that bone and blued stainless thing you did before, but that's a beauty. Do tell about the pommel nut.
Dan the pommel nut is just a piece of 3/8 stainless rod that I put in a lathe and machined with a female 10-32 thread that screws onto the rod on the tang. I took and cross drilled a 1/8 hole through the pommel nut so it can be tightened by inserting a rod or small screwdriver in the hole. If you don't have a lathe you can drill and tap the end of the rod ,insert a stud and spin it with a hand drill up against your 2x72 and grind the profile. You can put it in your drill press and use different files to finish to the desired profile. Colouring can be achieved by heating it SLOWLY and evenly with a propane torch and quenching in water, then applying a coat of wax to it. Colour changes from yellow - gold- dark golden brown - purple - blue, when you see the desired colour stop heating and quench.