We will start with your original post
This is a tanto in shira saya, probably from the Muromachi period, it is made of tamahagane, has hamon and hada, and is of the type of item that Kiku's ancestors made:
The knife that you have posted is a MODERN INTERPRETATION of a tanto....the context is extremely important, as are the terms used.
Best Regards,
STeven Garsson
Ummm... are you so stuck in your fancy knowledge base that you started to forget what a simple word "close" means...?
I by no means am infering the modern Kiku tanto is "accurate" to its history counterpart, I don't know why but apparently you over interpreted "as close as it gets"..