Greetings. This will be my first actual post on NMB other than replying in some threads. Here goes.
In 2016, I purchased my first "Nihonto". I put the word "Nihonto" in quotes because the mei on my sword bears the name of a smith held in low regard (at least it would seem so from other posts on NMB), Hattori Masahiro. From what I know of this smith, he mostly produced WWII Gunto/Showato during WWII. That said, he also produced medium grade Gendaito, presumably (by me) mostly pre-war. I've only found limited information on Hattori Masahiro, and cannot find an example of his mei that is executed as it appears on my sword, although this one is very close, the third character from the top appears differently, and I'm no expert.
At the time I purchased my sword, I had no reason to doubt I was purchasing a traditionally made Gendaito. I purchased the sword from a Japanese sword shop, and it shipped from Japan. I communicated with the vendor via phone and email. I did ask if this sword was traditionally made and if Tamahagane was used (rather than imported steel). I was told it was Tamahagane and traditionally made. Here is a link to the archived listing of the sword I purchased. Although I have no reason to doubt it's traditionally made, the hada is very fine and difficult to see unless viewed very close under led lighting. I would expect the grain to be more "loose" if Tamahagane was used (see the attached hada photo to see what I mean).
I know I have no art sword. I only care about the form, construction, and to know if it is a Nihonto/Gendaito. I only question this because of the repeated references to other swords made by Hattori Masahiro that look similar to mine as being "Showato" regardless whether they were traditionally made (Gendaito) or produced for the war. I understand that Showato or Gendaito literally have no bearing on a sword's method of construction, but as they are used among collectors, "Showato" is used to denote modern swords that are not traditionally made. In that context is how I would welcome any opinions on whether my Masahiro is "Showato" or "Gendaito".
I also welcome any opinions regarding my Masahiro's construction (Tamahagane or imported steel), the era the sword was made, pre-war, wartime, or post-war.
Thanks for taking the time to look.
Edit: In case it helps, I have some more pics from the seller that aren't archived. I made sure to download all pics at time of purchase. I believe the Tsuba and Habaki depicted are original. Obviously all the remaining Koshirae are newly produced. I also found another phone pic showing the full blade, although I doubt it shows any detail that hasn't already been shown.
Edit2: Added attached image of original vendor data that is not shown in archived link.