I recently inherited a Japanese sword from my grandfather who was given this sword by a Japanese translator he befriended when my grandfather was stationed in Japan following WWII. Our family has always been interested in the age of the sword and learning more about it. I have done a little research and have attached two photos. One side appears to contain what I understand to be the date, as I am able to make some numbers. I have included a photo of the other side, in case the age would make the non-date side of interest. I am primarily interested in the year it was made. I appreciate any help anyone is willing to provide.