Can this be from a Bad Parkerize Job

[INLAND44]

I found references to 'amer-lene' but I couldn't find out what it is or what its used for. In order to chemically remove markings stamped into steel, the chemical would have to dissolve enough steel to get below the depth of the markings. I don't think anybody uses anything like that in Parkerizing. Like already said, you're looking at two different carbines, one of which has been refinished at least once, which usually 'softens' the markings somewhat, and the other has had the markings removed, then it was refinished. The same gun can look different colors depending on the camera and available light. Parkerizing is particularly hard to capture as we see it naturally.