I think a re-blue.
The S&W logo/medallion is blurred from buffing.
The grit lines on the side plate don't go in any direction that would indicate a factory polish with the plate installed on the frame. From 1 oclock sweeping down to 7 oclock.
Plus there are heavier grit polish lines all over the gun in spots that were never removed when the polisher moved to a finer grit. Maybe even faint file lines in the metal here and there (right underneath the front side plate screw on the plate itself for one).
Look at the pic of the RH recoil shield. Click on it and then click on the pic itself again to really enlarge it.
Looks like file marks running down the back side of the shield then heavy buffed over for a shine.
The edges of the frame right along side the hammer have some either coarse grit marks under the shine or other coarse metal prep marks.
The cylinder recoil lug on the LH side of the frame (pic) is all rounded over and misshapen from it's normal crisp flat surface and sharp clean contour cuts from the factory.
It's a small part that is not installed in the frame during polishing. That so the it's not in the way of polishing that area of the frame.
When finished polishing, the clean, finished lug is placed in position and rivited in.
Lots of soft edges, not real bad, but soft. Not the sharp edges expected.
It's just what I see