In all the books I have on Confederate small arms, there is no mention of how they were finished. William A. Albaugh's Confederate handguns (and other books) includes a passage from a Feb 1864 letter from Col. Gorgas to Assistant inspector of Small Arms Capt Wescom Hudgins that states "In the pistol made by Rigdon, Ansley & Co, additional attention is required to prevent ring-boring, and in bringing the cylinder chambers to the true caliber; and rifling is hardly deep enough; front site projects into the bore; dimensions of the cone to be the same as Colt's; the cylinder must be case hardened, and Colt's lever catch substituted as soon as possible for the pin now used.
In some of the other books, there are references to Colonel Burton visiting various armories to instruct in case hardening and bluing processes.
As far as I know, there is no definitive description of revolver fnishes. Parts being left in the white is a distinct possibility; but I would more easily buy some bluing, browning, or case hardening finish to prevent rusting.
On a side note, the practice of using lye soap water in camp to clean rifles and pistols after washing ones clothes produced a finish known as Confederate Bluing on metal parts.
Fingers (Show Me MO smoke) McGee - AKA Man of Many Colts - Alter ego of Diabolical Ken; SASS Regulator 28564-L-TG; Rangemaster and stage writer extraordinaire; Frontiersman, Pistoleer, NRA Endowment Life, NMLRA, SAF, CCRKBA, STORM 327, SV115; Charter member, Central Ozarks Western Shooters
Cynic: A blackguard whose faulty vision see things as they are, not as they should be. Ambrose Bierce