Mystery SOLVED! Unlike in the movies where the protagonist finally would get the sword apart to find that it's the rarest most valuable sword ever created by the greatest swordsmith in Japan.....alas the blade does not seem to be signed. After hours of painstaking tapping, fiddling, gently prying, more tapping, more fiddling, more persuation etc etc etc....I got it apart. It is very corroded the pictures show. This pics are AFTER a bunch of elbow grease with 00 steel wool. It still looks pretty rough and if there was a signature I don't think it would be recoverable. Such as life. I am secretly happy that I get to keep this as a gift from dad and maybe I'll pass it down to my daughter some day. The question now is what is the best way to get this thing polished up and preserved. I got the mineral oil (light coating) part but what is a good way to get it up to shine like some of the one's I've seen online. It's still got a pretty good edge and I don't plan on trying to sharpen it. I guess the signature was on the kozuka and it's faded beyond being recognized.