I bought a tube of Flitz serval years ago and used it on a re-blued firearm. It removed the bluing where I started to clean the firearm. Afterward (wrong time), I read a little more closely and saw where it said it would not harm factory blued forearms but would take the blue off re-blued forearms. Skip ahead to today. I bought a Triple Lock and the seller thought it had been re-blued. I was cleaning revolvers and came to the Triple Lock. It does not appear to re-blued to me because the pins were not buffed smooth. I tested the Flits on the frame under the stocks and it did not damage the bluing. I then did the whole firearm with no loss of bluing. Can I assume the bluing is original? There are no markings from the factory saying it was returned for re-bluing.