Great Western’s standard revolver finish was always blue, but a traditional single action finish of blue with a color case hardened receiver was commonly available or an option that could be ordered. Great Western used two methods of color case hardening. To the discerning eye these finishes differ quite a bit in appearance and quality.
Through 1955, Great Western used a cyanide bath method, where the receiver frames were dipped in a boiling chemical solution that gave them exterior finish treatment. This cyanide finish was of middling quality. Frames done this way show watery, bronze / blue coloration. Revolvers with this case hardening are common up to about serial GW11000.
Through 1955 Great Western revolvers were finished blue / CCH more often than not, though the catalog described this as an upgrade selection. Per the catalog, plain blue was standard. Blue revolvers are quite a bit scarcer than blue / CCH among the first two years production however, and when observed those all blue examples are regularly deficient in polish or else overdone. It seems likely that proper polish and blue capabilities were lacking in the Great Western shop during this time. See the section on blue finishes for remarks on the ‘plum oxidation’ phenomena for investment cast parts used by Great Western.
By 1956 most of Great Western’s standard production was being finished in a satin blue of consistent quality. Great Western then ceased using the chemical bath to color its CCH frames. This may have been prompted by dissatisfaction with the quality of the cyanide finishes, or perhaps by new and evolving environmental regulations. In any event, a color case finish option remained but the method was improved, with frames color cased in a furnace with carbon pack (charcoal, bone, leather, etc). This was the artisan method used by Colt for the Single Action Army, and it provides a far more exquisite appearance. Color is typically puffy or thick rather than watery, and richer across the full spectrum of colors.
Now truly a special order option, the superior furnace and bone pack finish can be found on Great Western revolvers from about serial GW11000 through end of production. CCH finish Great Westerns are not common in this range. It’s probably right that examples with attractive bone CCH finish be contemplated as an especially collectable variation.