Driftwood Johnson how do you deal with this issue when you are evaluating condition?
I don't use a flashlight.
I simply examine a potential acquisition under normal room lighting.
I have never seen a description of exactly what 'freckling' is. I see it mentioned in catalogs all the time, but there does not seem to be a real definition. If there is, I don't worry about it.
Here is a S&W Model 36 from 1961. The finish is a little bit light or thin. My description. You can see tiny bare spots in the finish near the grip. I would call these freckles. Again, my term. Notice there is no rust showing in these freckles, just bare metal. If I tilt the gun just so, and get the light just right, I can see a little bit of red in the freckles. But normally they just look like bare metal.
This S&W 32 Regulation Police left the factory in 1924. A pretty deep pit on the backstrap near the right grip. No rust, at least none that I can see. The blue is pretty thin on the rest of the backstrap and some bare metal is showing through. I would call those freckles. I don't see any rust anywhere. Now, having said that, I suppose I should correct myself. I don't see any
red rust. What is rust anyway? It is iron oxide. Or corrosion. So while there is actually plenty of corrosion in that deep pit, I don't see any red.
Here is a nice little Colt 32 Police Positive from 1917. Plenty of freckling on the frame. Some actual dark brown corrosion where the recoil shield meets the frame.
Another view of he same Colt.
Here it is under a flashlight. I still don't see any red on the freckling on the frame.
So what is the red freckling? It is corrosion. Or rust. Usually occurring where the finish is very thin. As such, it is not under or above the finish, it is on the bare metal showing through small gaps in a worn finish.
When somebody says 95% (or pick any number you want) coverage of the original blue, that is a pretty subjective number. You might say 95% and I might say 80%. Who is correct? I have no idea. You would have to do a detailed study of the actual surface area of the gun, and then determine the actual surface area without finish. Nobody does that. I suppose if a very experienced dealer, and I don't mean the guy at the local gun shop, says XX%, I would believe him. Particularly if he sells literally thousands of guns every year. Like some of the big auction houses. A guy posting on a gun broker or some such internet site, if he says 95% original blue I will take that with a huge grain of sand. One reason I never buy old guns that I have not handled personally.
When I am looking at an old revolver, I just get an overall picture of the gun in my head. I look for visible rust. I look for wear on the blue. I also look for teltale signs of rebluing. Such as stamped markings that are a little bit faded from a polishing job. These can sometimes be very subtle, and I have been fooled a few times.
Bottom line, I don't concern myself with the % of finish. I decide what I will pay for the gun, and try to stick to it.
"I have also noticed that on most high condition antique revolvers ( pre WWII) I always see red freckling on blueing under bright light."
Since you have asked for my opinion, pre-WWII does not define an antique firearm. Pre-1899 defines an antique according to the BATF.