They did offer a factory nickel-plated 586; here's a link to a closed auction that has photos:
Is that what your gun looks like?
I have a sweet M-586...was under the impression that this was a model that always came blued from the factory...mine is metal plated, not really chrome, not really nickel....is this a custom job, and what might this finish be called.....either way, it's a shooter !!!!
The S&W M-586 The Distiguished Combat Magnum came in blue steel or nickel. If it is chrome somebody had it done. They polish that nickel to where it looks like chrome but it isn't. Shoot it and enjoy it as it is one of the best ever made.
Yes, it must be the polished nickel....it looks great and shoots even better...
and Baldy - I hear you ! !