Tags are not always found. On unused or seldomly used examples, maybe. The early real ones I have seen have that faint gold or yellowish look. It might be the light, but the one here seems to have it. I have also see them with oxidation, as JoeW notes. A good deal depends on how often the belt was worn and how early or late it was made. Postwar incorrect storage, in a damp place for example can drastically affect condition. If nothing else, I would try the black light test and see what happens.