Thank you everyone for your advice on my wakizashi - I very much appreciate your sharing your expertise. I have been trying to teach myself the correct terms by reading the glossary and the FAQs that are made available here on this website, as well as starting to read articles published elsewhere on the web.
I think my one last question at this point is to ask if there is any way to narrow down the timeframe and smith. What I understand so far is that its maker was a Bungo smith named Fujiwara Sadatsugu, and he may have worked sometime in the late Koto or during the Shinto periods (1500s, 1600s, or the 1700s). From your comments I understand that there are two smiths by this name noted in the reference lists (one who worked in the 1500s, and one who worked in the 1600s), but no one knows what their mei or blades look like. Also it could be an entirely unknown and unlisted smith from those centuries, or even one working in the 1700s who made good quality, very sturdy blades designed for reliable use by a working samurai. Is there no way to narrow this down within this 300 year period?
Thank you again for your kind patience in teaching me.
Jim