Old katana sword find.

I picked this up yesterday. I've always wanted a Japanese sword. The previous owner said it came from a friend and it was brought back in ww2. It looks older than ww2 with the cast iron guard and the wear on it. There is some silver spacers between the guard. The length is 36 inches total. A extreamly well balanced and very sharp. Some rust on the blade. I cant read Japanese and I looked around for info but I'm confused on it. Any help or information on this would be greatly appreciated. Thanks.