There are four metal finishes, that I can think of anyway. The barrel is draw-filed and polished to 180 grit abrasive cloth. It is browned using Neider's formula from Angier's book on bluing and browning. The solution I have was made up for me by a gunsmith in Marysville, BC He gave me a whole vanilla bottle full of it and I've been using it for several years now. I use a damp box made of plywood that has two incandescent bulbs - one in the bottom to heat the pan of water, and the other in the middle of the box to bring the inside temperature up to ~ 100 F. It is made using Biven's instructions. Each application stays in the box for ~ 3 hrs, after which time the barrel is rubbed down hard with a tight hard roll of canvas, to remove the surface scale. For a more polished look, use clean steel wool to card off the loose rust. Five or six applications will yield this somewhat matte but very smooth finish. I apply the solution using cotton balls I bought at the drug store. I pour the liquid into a shot cup. Here don't get it mixed up with the one with the single malt Scotch! The cotton ball is emursed and then squeezed out. the surface of the barrel is wet with the stuff using slow full length strokes. It doesn't hurt if you need to overlap, but I try not to rub the barrel. It does not 'copper' the steel like Laurel Mt. Forge's stuff. In this case, I started browning the barrel (and the lock) at 7:30 am and I took the parts out at 9:30 pm. I left then on the bench overnight, since I had company and killed the rust in the morning first by scrubbing with a supersaturated solution of baking soda and water, then poured boiling water over the barrel slowly lengthwise. This heats the barrel, flushes the surface, and then I oiled it with a towel and motor oil. The water evaporates from the heat of the steel. When it cooled off, I pulled the muzzle plug and unscrewed the breech plug (a brass plug about 4" long threaded on one end 3/4' x 16 and on the other 5/8" x 18). Then I rubbed the barrel down with a dry towel, and except for re-installing the sights and the breech plug, it's done. Whooo!
The lock I polished to 1200, but that's not really necessary if you're going to brown it. To 220 is lots. I polished the frizzen spring and the lock screws, and the trigger to 1200 grit paper, and fire blued them. I like the contrast between the shiny blue and the matte brown, though it looks good with a lock 'in the white' just as well.
The other screws- tang, lock bolts, top jaw, and butt plate screws are case hardened and burnished with a medium wire wheel. These screws are going to see some wear and abuse and case hardening them keeps them nice for a lot longer than not doing it.
The brass is polished to 600 grit and burnished with four ought steel wool. It's important during the last rub down with 600 that you go in only one direction - lengthwise.
So that's about it...hope I didn't miss anything.