Help with identification of an unsigned blade

[Joab]

Hello everyone, I hope I am putting this in the correct category... I recently purchased two swords, one of which I found the information about it on another gun form and with the help of the same member he directed me to here... The sword is unsigned as far as I can tell and these are the only pictures I have at the moment. I realize more pictures with better detail are needed and I will get those as soon as possible... I originally assumed that it was a fake or possibly a reproduction due to the red saya But upon further inspection I noticed that it seemed a bit older and was built fairly nice. My untrained eyes. Thank you in advance and I will put other pictures up as soon as I can

[Joab]

[Bruce Pennington]

Joab, Welcome!

 

FYI - he's been having trouble getting through to NMB (like some other folks) and has more photos.  He'll post more when able.

[Joab]

6 minutes ago, Bruce Pennington said:

Joab, Welcome!

 

FYI - he's been having trouble getting through to NMB (like some other folks) and has more photos.  He'll post more when able.

Thanks. It looks like I'm able to get on again. I'll try to put some pictures up as soon as I can

[Bruce Pennington]

Nagasa measurement is often useful.  And a couple of close shots, dark background, single light behind you - one of hamon (temper line) and one of blade tip.

[Joab]

4 hours ago, Bruce Pennington said:

Nagasa measurement is often useful.  And a couple of close shots, dark background, single light behind you - one of hamon (temper line) and one of blade tip.

Thanks. I have a bunch of pictures from yesterday but I was unable to put them up. I'll try again when I get home from work. I do have that particular measurement and several pictures of the temper line and the tip

[Joab]

[Joab]

[Joab]

Looks like my files are too big to look any more pictures.

[ROKUJURO]

On 8/12/2026 at 10:01 PM, Joab said:

.....I do have that particular measurement and several pictures of the temper line and the tip

Although you might have read that in many places, it is not a TEMPER line. This zone is made by HARDENING/QUENCHING. Tempering does not produce any visible effects on a blade. 

[eternal_newbie]

1 hour ago, ROKUJURO said:

Although you might have read that in many places, it is not a TEMPER line. This zone is made by HARDENING/QUENCHING. Tempering does not produce any visible effects on a blade. 

 

To be specific, the 'line' is a boundary of martensite crystal formations between two differentially-hardened portions of steel.

 

Because so many English sources and speakers use "temper"-related nomenclature when they really mean 'hardening', we generally just refer to it using the Japanese term hamon to avoid ambiguity/confusion.

[ROKUJURO]

9 minutes ago, eternal_newbie said:

.....because so many English sources and speakers use "temper"-related nomenclature when they really mean 'hardening', we generally just refer to it using the Japanese term hamon to avoid ambiguity/confusion.

The question may be allowed if we could improve our knowledge and learn new/old facts. Tempering is YAKIMODOSHI in Japanese, and YAKIIRE is quenching. That is not so difficult, and in the end, it helps understanding the metallurgy of Japanese sword making.

But nothing is more persistent than old habits, I know....

[Bruce Pennington]

Any one have an estimate of when the blade was made?

[ROKUJURO]

It is difficult with these photos and the condition of the blade. Only looking at the NAKAGO and the drilled MEKUGI-ANA, I believe it may be pre-WWII. 
There is no HADA visible and the HAMON without NIE or NIOI is strange, so it might have been made with modern steel.

I have sent Joab some advice for photo-making, so maybe he will come up with better images which will allow to see more.